Well, I picked up some .093 inch lexan (Home Depot's plexiglass subsitute), and cut it to fit my table. It's got some warp in it, but I'm currently weighing it down with a significant portion of my gaming library, so that should help flatten it out. It only cost ~$21/sheet at 36"x48", which means eventual replacement is unlikely to break the bank.
Apparently, neither home depot or lowes will cut plexiglass/acrylic anymore, so I had to get a plastic knife and a straight edge to do it myself. It's not great, but the jagged parts I hosed up are flush up against the lip of the table, so they're not overly noticeable.