What to do with deer mouse

A few months back we received a wild mouse as a feeder and it is now identified as a deer mouse. We didn't feed him off since he was a wild mouse and instead kept him in his own tub. With spring approaching I was wondering what to do with him. He's not a breeder and I really have no interest in keeping him as a pet and of course I can't feed him off to a snake.

So would it be legal and ok for the mouse to release him into the wild? We have some "forest" behind our house that he could scamper off into but I'm worried he won't be able to fend for himself. We got him when he was about 6 weeks old.

Where'd you get it?? And why wouldn't you just feed it off?

We got it from a reptile store that sells feeder rodents. They sometimes leave thier back door open when its warm and the mouse probably came in from outside and they probably thought it was one of their feeders escaped.

Since it was a wild mouse, I don't want to feed it to my snakes, regardless of it having lived with us for a few months with no signs of illness or parasites. I just make it my rule that my animals only eat captive bred feeders.

I would be more worried about him having spread something to the colony. I think that all things considered, it would have been safer to feed him off, than to risk damaging the colony. But even that is dicey; he could have come in contact with any number of toxins out in the wild. I personally would humanely euthanize it. I think that if let go, it would just get into your house and make a home there. After having had many expensive things chewed up, I have no sympathy for wild mice and rats!
I would say that it is unsafe to buy from a store that lets wild rodents come in contact with wild ones, within reason.