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 (
    10529, 10528, 10527, 10526, 10525, 10524, 
    10522, 10495, 10494, 10493, 10492, 
    10491, 10490, 10489, 10488, 10487, 
    10486, 10485, 10483, 10482, 10481, 
    10480, 10479, 10478, 10477, 10476, 
    10475, 10474, 10473, 10472, 10471, 
    10470
  ) 
  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 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_prices",
      "access_type": "range",
      "possible_keys": ["usergroup", "product_id", "lower_limit", "usergroup_id"],
      "key": "product_id",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 32,
      "filtered": 99.23484039,
      "index_condition": "cscart_product_prices.product_id in (10529,10528,10527,10526,10525,10524,10522,10495,10494,10493,10492,10491,10490,10489,10488,10487,10486,10485,10483,10482,10481,10480,10479,10478,10477,10476,10475,10474,10473,10472,10471,10470)",
      "attached_condition": "cscart_product_prices.lower_limit = 1 and cscart_product_prices.usergroup_id in (0,1)"
    }
  }
}

Result

product_id price
10470 1036.29000000
10471 1036.29000000
10472 1036.29000000
10473 1036.29000000
10474 1036.29000000
10475 1036.29000000
10476 1036.29000000
10477 1036.29000000
10478 1036.29000000
10479 1036.29000000
10480 1036.29000000
10481 1036.29000000
10482 1036.29000000
10483 1036.29000000
10485 1036.29000000
10486 1036.29000000
10487 1036.29000000
10488 1036.29000000
10489 1036.29000000
10490 1036.29000000
10491 1036.29000000
10492 1036.29000000
10493 1036.29000000
10494 1036.29000000
10495 1036.29000000
10522 1671.44000000
10524 1426.30000000
10525 1426.30000000
10526 1426.30000000
10527 1426.30000000
10528 1426.30000000
10529 1426.30000000