all tms shoot under 300fps stock as they are made for japan. Nothing over 1joul is allowed there.
to upgrade a tm to 380 do 3 things. First get rid of the nylon bushings. They tend to deform under the weight of a heavy spring. Next buy a metal bearing spring guide. The plastic tm ones like to snap. Third a spring. I personally use pdi 150% and get consistent 380 on .2 metal tech bbs.
tm honestly is just higher in quality control. Meaning you have less chance of gettin a lemon. This said they are getting out paced in todays airsoft market. Plastic bodies... Low fps... Plastic bushings.... There is now alot better out there for less money.
try ares, realsword, ca, and some other brands.
based on the rules I can't tell you were to buy these brand new... But there is now canadian retails importing guns with out clear bodies. Buying used you need to be aved and you will see even a wider range.
before you buy google the gun and read reviews on it. Don't try and be different for your first gun. Yah a uzi might be cool but find a tech that knows version 5 boxes. Something with a v2 or v3 is generally a newbie friendly gun.