I've got a Z33 (Nissan 350Z) six speed manual gearbox for sale. It comes with the shifter mechanism, prop shaft, and an adapter to fit it to an SR20 engine. The box has the bellhousing already machined so it is ready to be fitted.
The gearbox when I got it:
Machined bellhousing:
here it is compared to a stock Z33 box:
this is a really strong gearbox:
Here is the adapter fitted to my SR22VET:
Gearbox fitted to engine:
price: 850 GBP delivered for the whole kit.