there's several options as far as rebuild kits go. when i was doing my research the best deal on a rebuild kit was from JEGS i believe, $320. but when i kept on doing research i kept on finding that if your gears are grinding you may need to replace gears as even if you replace synchros that it may not completely fix the problem. the gear kit i was looking to replace my set with was an OEM Zspec gear kit, $450. this has a 2.95 first gear ratio over the 3.35 GT T5 first gear ratio. also you may want to look into Bad Shoe Productions for a in depth step by step how to rebuild your T5 DVD. alright now this is my conclussion on the idea of rebuilding my own T5.
450
+320
+ 35
+ 50 for misc crap you might need
-----
805 total dollars
that doesn't seem bad a basically brand spanking new trans for 805 dollars. okay now you have to do it yourself and hope you get it right (my fear). next if you don't get it right you have to do it again and figure out where you went wrong. i ended up buying a professionaly built transmission for 1,000 dollars. now i did get a really good deal. i got the Zspec ratios (2.95 first and .64 OD) and the trans is rated for 350 ftlbs torque and 450 HP. the sticker price is 1002 +150 in freight + tax and if your in put shaft on your trans is buggered like mine was they will charge you another 100 dollars for the machine shop work.
i was able to get my trans for 1002 because i drove to the shop a few hours north so no freight costs, payed cash and waved the tax, and got 75 dollars credit for an old bellhousing that bolts up to the T56 trans. so he sold me the trans at sticker price.
so for a little bit more you get a lot of piece of mind. IMHO.
if you decide to go the route of buying that trans pro i deifnately recommend going through Astro Performance transmissions. i have been to their shop and they have a top notch production going on. Tony the man who deals with all the sales is a great guy to work with. he really knows his stuff and was willing to help with everything i needed from tear down to cash exchange at the shop.
here is a link to the trans i bought.
Astroperformance.com - Your Manual Drivetrain Specialist