Mac G4 PowerPC win 10.5.8

Is there a current or previous version of Parallels ( even if no longer sold) that works with this hardware combo?

 

no. parallels only works on an intel mac. MS had a product they purchased from connectix that allowed a powerpc mac to run earlier versions of windows on the mac, but since the emergence of intel-based macs the product was eventually discontinued.

there is a product called guestpc by another vendor that supposedly works by emulating (not virtualizing) an intel system on a powerpc and supports up to windows xp - no vista, no 7, etc.