You probably won't be able to find it again. Gitman offers some customizations for their orders (pockets and collars) and it is harder to find double pocket shirts. Frances May is probably the only one that stocked it.
if im more of a small than medium in gv, though medium looks aight (almost perfect in the chest and shoulders whereas small is sometimes tight) you guys think I can take a medium to a tailor and fix it up or is just gonna be shit?
Yes, you can. From what it sounds like, I'm assuming you have a larger chest and broader shoulder so the box pleat billowing doesn't sound much of a problem for you. You can a) dart the back at the waist similar to Epaulet or b) take in the sides for a nice taper. Darting is cheaper than taking in the sides.