dont buy a kit... IMO they are way overpriced!!! for keeping the engine stock i would suggest building your own kit, mine cost me $1500 on the stock engine! here is a layout of what to look for and some prices...
turbo - 14b = $150 for a good one
you will need a oil pan off of a 4g63 motor - i paid $25 from a local junkyard, you will need to by some piping for the oil lines and water lines, i spent $50 for braided steel lines and spent $15 on fittings off of ebay
Manifold + Exhaust (the expensive part) you could have it custom made like i did or you could go buy a complete system, mine cost about $450 for everything complete...4-1 manifold, 3" turbo back w/o cat and greddy sp canister.
Intercooler + Piping - i went with the side mount cause i wanted to keep it a sleeper <- (that didnt last long) go to the junkyard or on ebay and get a stock SMIC from any year will work, around $50... piping - go to your local home depot and buy up some rubber fittings and some 2 1/2 inch PVC piping and some elbows (save your receipt so that you can return any that you dont use) i'm not positive on how many pieces that you need but i think i paid about 45-50 for everything... them damn elbows are the expensive part! but its cheaper than buying the kit piping and it works the same, just make sure you use a lot of PVC cement so you dont get any Boost leaks! now for the BOV... 1st gen BOV works just fine, all i did was drill a hole in the upper intercooler piping and screw, clamp, cement, and super glue it to the pipe (if its done right it doesnt look to bad) now the nice thing about using the PVC pipe is you can paint it any color you want, although i would suggest using hi-temp paint!
Injectors + fuel pump - i went with the stock 450cc injectors from a 97 GST, they work just fine for the boost you will be running, anywhere from $20-$70, now for the fuel pump, its not a nessecity but i wouldnt run high boost for long periods of time without upgrading (when i say high boost i mean 7-10psi) i just upgraded to be safe and i would suggest it too, i went with the walbro 190lph - i dont remember the price off hand but i think it was about $80-$100.
for controllers, i got Apexi AVC-R for my boost controller and Apexi S-AFC to control the injectors and fuel pump (you do not need it if you dont upgrade the fuel pump) - for a boost gauge i went with autometer cobalt, i spent about $550 total for everything off the internet (
www.ebay.com )
dont quote me on all of those prices but most of all of them are what i payed, you might be able to get it cheaper, maybe more... i kinda wrote this up quick so if i forgot anything i will make sure to update asap! hope that helps EVERYONE THAT HAS A QUESTIONS ABOUT TURBOING AN ECLIPSE RS/GS!!!