Yeah, petco is only going to sell frozen mice. They don't have f/t rat pups, only small medium and large adult f/t rats, they won't sell you the live ones as feeders, or if they think you're going to use it as a feeder, and even if you buy them sneakily, they're still way more expensive than what you would pay for a feeder mouse/rat elsewhere because they're intended as pets. Search around and see if there are any local reptile stores. This place is in Boise, idk how close to you it is, but they might carry better live and frozen feeders than petco. Probably more knowledgeable and can identify the snake too. If you feel you want to keep the snake long term, you can order bulk f/t rats online from lots of different places and usually for much cheaper, but it takes a couple weeks for orders to ship, so stock up locally until then. I get my rats from Big Cheese, and so far I haven't been disappointed in quality.