The wii set to 60hz 480p will be pretty darn close to vga sync rates - the wii I think only allows 480p if component cable inserted.
The conversion from component to rgb is a bit tricky, but google says products already available for that:
http://www.ciao.co.uk/Nintendo_Wii_RGB_Cable__6595510HSync and VSync are a bit more tricky so that product won't probably be able to be converted, i would say wait a few more weeks and ask google again.