Okay, I'm an idiot.
I thought you were talking about MUA2. I guess MUA and PS2 just blended together for me.
If you're talking MUA1 PS2, then yes, you can use them. The levels use something called _combined.igb (might be off on the name). This is the main level geometry, but also has props like barrels in it. You should be able to use that and the XMLBs.