If it were my pond that had the apparent high number of YOY RES AND I had access to a nearby mature SMB fishery, I would definitely make an attempt to get a few 8"-14" SMB for transport to my pond as tools for consuming small sunfish be they RES or possibility those unwanted BG. Temperature Stressed YOY RES would be very easy catch food for predators big enough to eat them. The main negative of doing this IMO would be the larger SMB might eat a few of the 4"-6" stocker smallies.

When holding and transporting a few mature SMB be sure to have ample water for hauling to minimize stress as mostly low dissolved oxygen on the smallies that had already been stressed due to the angling and physical handling. One does not want to go to all the trouble of going and catching a few smaller bass and then have them die after restocking. IMO one cannot have too much water for hauling mature fish. IMO 10 gallons of bubbler aerated water minimum for EACH fish would be adequate IMO for holding and hauling them for 1 to maybe 3 hrs. Adding one pound of non-iodized salt to the hauling water of around 40 gallons will help reduce hauling stress. A plastic barrel with the top cut off or a large plastic garbage can would be good transport containers. You can put a garbage bag liner in the container & tie it shut to keep the water from sloshing out of the container.