You'd only need power for aeration, and can easily run buried air line that distance. The feeders are solar powered.
I have probably 60 or so adult LMB in my pond. Most are 17"-18" long and run between 3.25 to 4.5 pounds. BG are 4" to 10", and the larger ones are over a pound (gotta catch one and weigh it). Most 8" BG are running .6 - .7 lb. I have roughly 35 tagged LMB in the pond, and I'm removing every LMB caught that is NOT tagged. The tagged LMB are feed trained, the non-tagged ones are not, but some have learned to eat pellets from the others. Not many, but some. I was BG light, due to highly fluctuating water levels and not enough cover for small fish to hide in, so I stocked probably 2-3,000 BG in the past few years from 1" to 8", either excess fish from Cecil Baird or stunted BG that were removed from some clients ponds. The LMB responded by putting on a LOT of weight, even if not feed trained. 17.5" 4 lb. 4 oz.
If you stock feed trained fish, I think you could keep 20-30 LMB in the pond, and have 10" BG. BUT, if a half acre pond, if you will feed, I would give some serious thought to HBG and HSB, maybe with some feed trained SMB thrown in there for diversity. If you wanted fish for the kids to catch during the cooler months, look at feed trained YP. In a smaller pond, the HBG/HSB mix is easier to manage than LMB/BG.