The stuck shed is the least of his problems as long as his tail tip is clean and there's no ring of it completely encircling his body. Keep his temps correct and his humidity on the high side and he'll likely deal with it himself.
If you don't have PAM or the NIX/RID mite solution then make some and treat his enclosure, paper substrate, and hides the day before you bring him home if you do get him. I'd wipe him down with a white paper towel dampened with either water or Reptile Relief before leaving the store to show the employees whether or not he's got mites.