A catalog of all the HID ballasts Advance makes...
http://www.advancetransformer.com/ec...hid_lookup.asp
Plug in ANSI code M80 (250W) or M81 (150W) and you'll find the HQI ballasts that Advance makes. You'll get the part #'s and spec sheets (you'll still have to order the ballast from somewhere but at least you can read up on them).
I'm not 100% certain of this, but I think Advance might be the only maker of HQI tar ballasts. I don't think Venture or the other better known ballasts makers do, but if I'm mistaken maybe someone can point me to some info.