I don't think so, as you'd need to use spacers to compensate for the late-style offset, and you'd likely have problems with the rears.
Ruf wheels for your generation of car are 17".
The 8" & 10" x 17" wheels are for the CTRs. (Which apparently have wider rear flares than SC/Carrera, but it's subtle).
The 9" & 10" x 17" wheels are for 930's.
The Ruf wheels for SC/Carrera flares are 8" & 9" x 17:
The 8.5" & 10" x 18" wheels are for 964/993/996 etc.
http://www.rufautocentre.com/parts/pdf/wheel.pdf