Pat try and get a parts book or try an online parts book like cmsnl.com and google the part numbers, sometimes comes up trumps.
Also helps if you phone Granby's or motoward with the numbers and they can check their fiche.
I use peeks polish, it can be used on fibreglass and plastic. I'm not convinced you need that sort of polish though, just soapy water.
I use motrax protect and shine
I use it on exhausts too
feel for you Jordan .
don't get too pissed over it. You now have the incentive you need to DIY, that's why I always do my own or have a mate to help do things.
ask away here for advice and get as much advice as you want from us
as with all custom applications, modifications would be necessary.
eve thought of modding the original seat?
try RK leighton and ask them what you are thinking of doing, they can remold the foam and recover the seat pan
give it a tune up first, check timing and valves.
carb could need overhauling if the above doesn't work.
get yourself a manual and read the troubleshooting section too