Shorten stock is no problem, but the bbl work will likely go out of the area to Briley in TX or Wright's. Either can be found via usual search. One of the best all around local gunsmiths is Pat Laib and he makes the round of several clubs every week picking up work and dropping off completed projects. Pat is generally one week. Start with Pat. Allow him to walk youthru the process. One of his PU points is Metro Gun Club in Blaine.
Just a suggestion, but before you invest a lot of money in chokes (if you are shooting trap) why not shoot the fixed chokes that come with the gun. The bottom barrel should look after all the singles and short yardage targets, and the top barrel should be fine for most of the longer range targets, with the added bonus of not having to worry about the chokes rusting in etc. Pat Laib can certainly look after your other needs.