8' diameter and 2' deep is too shallow and too narrow for me and ofr that kind of coin.
If you are trying to do this relatively inexpensively, why not go for the classic above-ground pools? Some quick searching suggests you could get one that's 2x the diameter and 2x as deep for under $2k, delivered. That's more than 8x the volume, and deep enough where you could really splash around.
Of course, my personal opinion would be to join a club pool that's big and I can swim laps and where they take care of all the maintenance. $1k will pay for a family membership for two full summers at a very nice club near us. YMMV.