No such thing as competitions in Canada.
It's been tried in HK and the Philippines I believe but seriously it's kind of retarded.
There are however large milsims. They're not "competitions" but just really large games with a large turnout (200+ players).
The easiest upgrade would be to buy a drop in gearbox like the Action V3 gearbox and replace the stock gearbox. Note that it may get seized (as a "receiver") but since it's not prohibited it will get released if you contest the seizure.
Either that or if you're feeling a bit ambitious get a Modify FTK for V3 gearbox.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE