On Ebay now (in the US) FireGL X3 cards for $25 with shipping (seller only has US shipping listed).
Over ten available. I just purchased one myself.
These can be re-flashed with a Mac BIOS and can be modified to be compatible with G4 and G5 Macs.

http://www.ebay.com/itm/ATI-Fire-GL-X3-256mb-AGP-404563-001-Dual-DVI-Graphics-/280758459783?pt=PCC_Video_TV_Cards&hash=item415e821d87

International user: If you'd like to buy one of these, you can have it shipped to me and I'll ship it to you. Then all you'd have to do is reimburse me for the additional shipping charge.
Further, if you'd like the card flashed for Mac use, I can do that (as well as tape over pins 3 and 11 for G4 use).

Note - I can't guarantee that a MorphOS driver will ever be written for R400 cards. While it has been discussed, I have no idea when (if ever) this will be available.


[ Edited by Jim 31.03.2012 - 15:18 ]