Gamo parts needed!

I need to replace my lock up plunger and spring on my Gamo Mach 1. I pulled the barrel and removed the plunger and filed the rear of the slot to allow the plunger to move a little farther front which worked but I feel I only bought a little time. I know that there are aftermarket triggers available so I was wondering if anyone makes lock up plungers. I have read that Gamo will only ship to a ffl dealer which I can contact to receive the part but not sure how much that will cost and don't want to if I don't have to. Thanks, Gary.