IMHO, instead of buying the ADC Studio Display CRT and a DVIator, just get a high quality NEC or Samsung CRT and connect it to your VGA port. It'll cost the same or less than the Studio Display/DVIator combination, and you'll be getting a brand new monitor of very high quality. NEC's highest end 17" CRT will do 1280x1024 resolution at an impressive 85 Hz - the Apple does the same resolution at 75 Hz, and most 17" CRTs can only do that resolution at an unacceptable 60 Hz.
If you already have the Studio Display, though, maybe you should go for the DVIator.