If he seems fine and is eating/shedding/pooping normally then it sounds like it's only a small kink.
In which case, chances are he should be fine. If the kink is only a small one, then there also a good chance it will grow out over time. Sounds like there is no reason he shouldn't lead a full and happy life.
Not sure about putting it up for sale in a pet shop. Maybe with a discount?
Might be better keeping him off the shop floor for a few months to see how he develops.