Personally, I'd make one out of a 50-ish quart cooler (like
this one), drilling a hole in the top and running a strong aerator in there and keep some ice in there to keep cool. It can double as a seat, knot tying spot, or whatever else even when full, and you can also fill it up with cold brewskies for scouting/catch-and-release days. That's a pretty cost-effective way to test the waters, so to speak, before taking on a bigger and much more expensive project.