I grow a lot of fruit trees from grocery store seeds so have no idea what they are. However, just by chance last year, my husband got a deal on some fruit trees that were about to be thrown out at end of season from
Tractor Supply and we ended up with 3 "Contender" peaches among a few other species. I had never heard of it so I looked it up and it turns out that Contender is one of the hardiest peaches you can grow -- USDA Zones 4 to 8. It's also supposed to taste really great, so you may want to try it. I'm sure it would do well in zone 5b.