SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    105228, 105227, 105226, 105225, 105224, 
    105223, 105222, 105221, 105220, 105219
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00073

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_prices range usergroup,product_id,lower_limit,usergroup_id usergroup 9 20 Using where

Result

product_id price
105219 1.69000000
105220 1.69000000
105221 1.69000000
105222 1.69000000
105223 1.69000000
105224 1.69000000
105225 1.69000000
105226 1.69000000
105227 1.69000000
105228 1.69000000