MAudio Delta 1010 PCI Digital Recording Rack Mount and Mac Pro

A great digital audio rack-mount converter is MAudio's Delta 1010. It uses a PCI card for which I heard one could get a replacement PCI-X interface card, but such is not available for PCI-Express slots which are all the Mac Pro workstations have.

Does anybody know of a solution? Perhaps an interface that converts PCI or PCI-X to FireWire, USB, or PCI-Express? In other words, any way at all to make use of equipment for which the manufacturer doesn't supply a Mac Pro'able interface?

(And my apologies if this is just a silly question; I'm not super hip to all the hardware stuff.)

Thanks,

Rich Apple