SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  IF(
    shared_descr.product_id IS NOT NULL, 
    shared_descr.product, descr1.product
  ) as product, 
  companies.company as company_name, 
  products.product_type, 
  products.parent_product_id 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'en' 
  LEFT JOIN cscart_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  LEFT JOIN cscart_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN cscart_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN cscart_categories ON cscart_categories.category_id = products_categories.category_id 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  AND cscart_categories.storefront_id IN (0, 1) 
  LEFT JOIN cscart_ult_product_descriptions shared_descr ON shared_descr.product_id = products.product_id 
  AND shared_descr.company_id = 1 
  AND shared_descr.lang_code = 'en' 
  LEFT JOIN cscart_product_restricted_countries AS prc ON prc.product_id = products.product_id 
  AND prc.country_code = 'US' 
WHERE 
  1 
  AND companies.status IN ('A') 
  AND (
    products.usergroup_ids = '' 
    OR FIND_IN_SET(0, products.usergroup_ids) 
    OR FIND_IN_SET(1, products.usergroup_ids)
  ) 
  AND products.status IN ('A') 
  AND prices.usergroup_id IN (0, 0, 1) 
  AND (
    (
      1 
      AND products.product_id IN (
        43249, 43250, 43251, 43252, 43253, 43254, 
        43255, 43256, 43257, 43258, 43259, 
        43260, 43261, 43262, 43263, 43264, 
        43265, 43266, 43267, 43268, 43269, 
        43270, 43271, 43272, 43273
      )
    ) 
    AND companies.status IN ('A') 
    AND prices.usergroup_id IN (0, 0, 1)
  ) 
  AND (
    products.available_worldwide = 'Y' 
    OR prc.country_code IS NULL
  ) 
GROUP BY 
  products.product_id 
ORDER BY 
  products.timestamp desc, 
  products.product_id desc, 
  products.product_id ASC

Query time 0.00136

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE companies ALL PRIMARY 1 Using where; Using temporary; Using filesort
1 SIMPLE products range PRIMARY,status PRIMARY 3 25 Using where; Using join buffer (flat, BNL join)
1 SIMPLE shared_descr eq_ref PRIMARY,product_id,company_id PRIMARY 13 toolboxdigitalshop_dev.products.product_id,const,const 1 Using where
1 SIMPLE prc eq_ref PRIMARY PRIMARY 9 toolboxdigitalshop_dev.products.product_id,const 1 Using where; Using index
1 SIMPLE prices ref usergroup,product_id,lower_limit,usergroup_id usergroup 3 toolboxdigitalshop_dev.products.product_id 1 Using where; Using index
1 SIMPLE descr1 eq_ref PRIMARY,product_id PRIMARY 9 toolboxdigitalshop_dev.products.product_id,const 1 Using where
1 SIMPLE products_categories ref PRIMARY,pt pt 3 toolboxdigitalshop_dev.products.product_id 1 Using index
1 SIMPLE cscart_categories eq_ref PRIMARY,c_status,p_category_id PRIMARY 3 toolboxdigitalshop_dev.products_categories.category_id 1 Using where

Result

product_id product company_name product_type parent_product_id
43273 Harmony Heart (Original Mix) Toolbox Digital Shop P 0
43272 Activation (Original Mix) Toolbox Digital Shop P 0
43271 Sunshine (Original Mix) Toolbox Digital Shop P 0
43270 Play Girl (Original Mix) Toolbox Digital Shop P 0
43269 Dirty Disco (Original Mix) Toolbox Digital Shop P 0
43268 You Want Some (Original Mix) Toolbox Digital Shop P 0
43267 Yo DJ (Original Mix) Toolbox Digital Shop P 0
43266 War (Original Mix) Toolbox Digital Shop P 0
43265 Booty Breaker (Original Mix) Toolbox Digital Shop P 0
43264 Genetix (Original Mix) Toolbox Digital Shop P 0
43263 Sing To Me (Original Mix) Toolbox Digital Shop P 0
43262 Drop It (Original Mix) Toolbox Digital Shop P 0
43261 Faithfulness (Clowny Remix) Toolbox Digital Shop P 0
43260 Hard Times (Original Mix) Toolbox Digital Shop P 0
43259 Destiny (Original Mix) Toolbox Digital Shop P 0
43258 Climax (Original Mix) Toolbox Digital Shop P 0
43257 Headbanger (Re-Work) Toolbox Digital Shop P 0
43256 Bring It Back (DJ 490 Powerstomp Remix) Toolbox Digital Shop P 0
43255 Need You Now (Original Mix) Toolbox Digital Shop P 0
43254 Strait Jackket (Original Mix) Toolbox Digital Shop P 0
43253 Hardest Bass Around (Original Mix) Toolbox Digital Shop P 0
43252 Break Me (Original Mix) Toolbox Digital Shop P 0
43251 Move It (Original Mix) Toolbox Digital Shop P 0
43250 Blue Eyes (Original Mix) Toolbox Digital Shop P 0
43249 Come On (Original Mix) Toolbox Digital Shop P 0