If you have no luck with Adrian or the other traders then maybe try a PM to a moderator called Nic (nissanman312) to see if he can get you the belt part number as he owns a 2010 370GT with a Stillen supercharger set up.
Link: http://www.350z-uk.com/user/18462-nissanman312/
Hope that helps.
I think Adrian from TORQEN should be able to help you with everything you need.
Link: http://www.350z-uk.com/forum/228-torqen/
Other traders are available in the professional traders section on here if you have no luck with him or want to try others as well.
Link: http://www.350z-uk.com/forum/93-professional-traders/
Why did you have to say that, ...just googled them, found Ian's motor still on their site & now I'm browsing cars that I'd like!!
http://jm-imports.co.uk/index.php/1998-nissan-skyline-r33-gtr-series-3/
There are so many great traders on here Josh that could help you out with all the parts you'll ever need.
All the professional traders are here: http://www.350z-uk.com/forum/93-professional-traders/
Member traders here: http://www.350z-uk.com/forum/38-member-traders/
Secondhand parts etc here: http://www.350z-uk.com/forum/14-the-trading-post/
Have a look around as it's all on here.
In fairness though I understand PC's are better in so many respects than consoles but for my needs I just find the consoles so much easier to get on with.
Great stuff all.
Always fancied doing this myself but never got around to it.
Maybe one day but I need a decent driving game on the PS4 before I go to all the trouble of making a driving rig set up. Hopefully "Gran Turismo" later this year.
I'll have a look for it at their house as soon as I can for you and will let you know either way.
The colour is a 1996 JDM Subaru silver that I had laying about in the garage from painting my Impreza many years ago. I removed all the surface rust on the bracket and then modified it slightly by removing some of the metal so that it didn't foul my air intake pipe on my supercharged Zed.
Really hope I can find it for you now but keep looking just in case I don't find it.
Probably easier if you say you need the passenger side or drivers side as the above description would depend on whether you're talking about being inside the car or looking at it straight on.
If you need the passenger side one then I "may" have one at my parents house, ...won't be able to go there & look until the weekend though but you could have it FOC if I do have it. Don't stop looking though just in case I can't find it.
I have modified the bracket though slightly although it will still do the job intended. Picture below of my old bracket just to be sure we're talking about the same part.