Somewhere in my junkpile I have an original 4Mb 3DFX PCI Voodoo card (whoo!) with the VGA loopthrough, if you want I will dig it out so you can have 3D. I may even have a few Riva TNT2 (ahhh!) PCI cards lying around too, that way you can get the GL Quake '97 and GL Doom patches working in proper 3D, if memory serves me correctly. Sorry, I can't run to Vesa Local Bus cards LOL.
I think these guys need some period hardware upgrades mate. Is that Soundblaster Pro you mention the one I sent you?