Greddy Turbo?
 

As I seem to understand the product seems to be discontinued, so the question would be what would my "GOOD" alternative be, looking at a max of 9k spending range.

Maybe a tad more.

Thanks

2nd hand Greddy kits still come up every now and then. Check the For Sale section.

Regardless, you need to throw a lot of time into researching all the different options before throwing $9k at it. Check out a bunch of turbo build threads in the Major Horsepower Upgrades section. If you have problems finding what you're looking for, go to Google and type this into the search box:
site:rx8club.com turbo build

https://www.rx8club.com/rx-8-parts-s...rt-out-254452/
2k for his which has 20k miles on it.

I'll sell you an entire Rx8 with the kit on it for $13,000 :lol2:

https://www.rx8club.com/canada-sale-...bo-rx8-253198/

Buying a used Greddy kit is far more cost effective than buying a Greddy kit new because so many things need to be changed after you install it.