The YT 175 was only produced for two years, from 1982 - 1983. There are a few differences between the two, a few are decals are different color, and the intake manifold size is smaller on the 82 than 83. Both model 175's were chain driven, and the 82-83 175 shares many of the same parts as the 82-85 YT 125, including the throttle cable. The 80-81 YT 125s are a LOT different though, and not many parts will swap over (frame wise) and some motor changes on bottom end, and throttle cable is different I believe. The jets are pretty close if I remember right, and should be fine to use between both years YT175. I think the main jet would be easy to find, and should be able to find at any motorcycle shop, otherwise you could look for a carb rebuild kit, which run about $20, and would have all the jets you mentioned, and everthing else to rebuild your carb. Good luck, and post up some pics!
THE 80's RAGE! Currently owns:
81, 85 Yamaha Tri Moto 125
83 Yamaha Tri Moto 200 x2
82,83 Yamaha Tri Moto 175 project
85 Yamaha Tri Z 250
84 Kawasaki Tecate 250
84 Honda ATC 70
85 Honda ATC 350X
84 Honda ATC 250R
(2) 84 Honda ATC 200x
82, 83 Honda ATC 185s
81 ATC 200
Lots of other parts and bikes