If you stock anything but starter size RES at initial rates then you've got to remember that you're stocking a larger size.
The only recommended stockings of adult fish from a definite source, that I know of, is stocking 30 adult crappie per acre. Which is from the
missouri aquaguides . Since you have no LMB present but you do have 8" CC, the best help I can give is to stock 40 RES in the 4"-6" range. That is about 30 RES per acre, give or take depending on whether you stock for a 1.25 acre pond or a 1.5 acre pond.
If you stocked 500 "pure" strain bluegill than 40 adult(4"-6") RES per acre should be able to spawn fairly well and since they will probably be the same size if not bigger they'll spawn a little better than starter size RES. Though RES have lesser spawns they should be able to fit into the chain, hopefully, better at that stocking rate and size.
My main concern for you isn't whether or not the redears will establish but is that without an efficient predator the bluegill, redears, and crappie will stunt, eventually leaving you with nothing but a bunch of fat catfish.
I pretty much agree with theo just a slightly larger size and lower initial stocking rate.
I would argue the point of stocking HSB though. I am heavily biased towards LMB. If you can't tell
.