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 (
    5750, 7013, 5739, 5727, 944, 478, 985, 
    525, 2478, 10284, 2527, 2490, 1406, 
    508, 1266, 1428, 1263, 2471, 2576, 2620, 
    1256, 1319, 1273, 4526, 2502, 2473, 
    2565, 2580, 2550, 2599, 2503, 2602, 
    3049, 2540, 3046, 3053, 4767, 2685, 
    2623, 5037, 8398, 4744, 2499, 3055, 
    2581, 2631, 2519, 8399, 5053, 8397, 
    4789, 8395, 5027, 5045, 5051, 10140, 
    5048, 10222, 10228, 10435, 10395, 10233
  ) 
  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 0.00187

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "50.16"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "range",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "key": "product_id",
        "used_key_parts": [
          "product_id"
        ],
        "key_length": "3",
        "rows_examined_per_scan": 77,
        "rows_produced_per_join": 15,
        "filtered": "19.99",
        "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_prices`.`product_id` in (5750,7013,5739,5727,944,478,985,525,2478,10284,2527,2490,1406,508,1266,1428,1263,2471,2576,2620,1256,1319,1273,4526,2502,2473,2565,2580,2550,2599,2503,2602,3049,2540,3046,3053,4767,2685,2623,5037,8398,4744,2499,3055,2581,2631,2519,8399,5053,8397,4789,8395,5027,5045,5051,10140,5048,10222,10228,10435,10395,10233))",
        "cost_info": {
          "read_cost": "48.62",
          "eval_cost": "1.54",
          "prefix_cost": "50.16",
          "data_read_per_join": "369"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_prices`.`lower_limit` = 1) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}

Result

product_id price
478 1055000.00000000
508 935000.00000000
525 1675000.00000000
944 1395000.00000000
985 1205000.00000000
1256 130000.00000000
1263 1120000.00000000
1266 1130000.00000000
1273 1760000.00000000
1319 510000.00000000
1406 760000.00000000
1428 390000.00000000
2471 1455000.00000000
2473 1032000.00000000
2478 850000.00000000
2490 599000.00000000
2499 1384000.00000000
2502 1446000.00000000
2503 1027000.00000000
2519 173000.00000000
2527 93000.00000000
2540 527000.00000000
2550 440000.00000000
2565 282000.00000000
2576 276000.00000000
2580 975000.00000000
2581 713000.00000000
2599 483000.00000000
2602 379000.00000000
2620 116000.00000000
2623 839000.00000000
2631 479000.00000000
2685 322000.00000000
3046 450000.00000000
3049 823500.00000000
3053 4454100.00000000
3055 2556120.00000000
4526 1300000.00000000
4744 390000.00000000
4767 310000.00000000
4789 1485000.00000000
5027 249000.00000000
5037 93000.00000000
5045 256000.00000000
5048 290000.00000000
5051 125000.00000000
5053 100000.00000000
5727 2005000.00000000
5739 1300000.00000000
5750 1655000.00000000
7013 2149000.00000000
8395 108000.00000000
8397 364000.00000000
8398 251000.00000000
8399 354000.00000000
10140 766000.00000000
10222 755000.00000000
10228 584000.00000000
10233 1030000.00000000
10284 880000.00000000
10395 744000.00000000
10435 1147000.00000000