All,

Where may i purchase a threaded barrel for my FNP-40?

On a side note, is it worth converting to a 9mm if threaded barrels are available for those?

Additionally, is there also a source for trigger upgrade for these pistols? The factory trigger could stand to be tuned up like a 1911's.

Talk to EFK Firedragon about a threaded barrel.  They list .40SW to 9mm and .40SW to .357SIG threaded conversion barrels on their website.  I don't see why they couldn't do a .40SW barrel for you since the outside dimensions are the same.  They may in fact already make them and their website may just be screwed up.  I don't know though.  I'm only using them for conversion barrels for my FNP-40 and FNS-40.