They are pricey at ebay >$1000/lb. Even so a few can become millions but you would need to have a way to jump start the introduction by having away to reproduce them without a fish presence. A couple of other ideas ...
Hyalella Azteca ---
https://goliadfarms.com/shop/gammarus-scuds/Also if you have silty bottom without submergent vegetation covering ... then I read of a very interesting way to collect Hexagenia mayfly eggs. When the hatch is on in a nearby lake, drive up to bank at night, the paper referenced that they used a boat ramp. Shine the car lights onto the water. Below your car lights, have tub filled with water. You will see mayflies coming into the light as the skip(fly intermittently) across the water. At the light they will settle to the water and lay eggs. Distribute these eggs in your water. These critters were exceptionally important in my home town's munincipal lake hatching from June through August with a peak in June. But they won't benefit from a weedy pond the way PK shrimp and scuds would.
Gambusia are native in your area. If you don't have them, you can scoop them up with fine mesh net from the dollar store. Many times park ponds have them. It doesn't take many as they are resilient fish. Time introductions in May or June.
If you have alot of BG that are small then they probably have limited the secondary trophic level. Reducing their number will allow secondary trophic organisms to flourish. More LMB in 6" to 12" well help ... remove any LMB > 14 inches that might eat your 5" - 7" LMB. If there is no statewide length limit for LMB in your state you might find a farm pond with an abundance of LMB as a source of supplemental LMB. You want LMB that are feeding on BG if you supplement.
