The rims themselves? Almost nothing. AVA were kind of soft, and were budget rims. Unless they're NOS, figure $20 bucks in most markets.

If they're full wheels, with Campagnolo hubs, then maybe $80-150 for the complete wheels, or $100-200 for just the hubs on eBay. (Yes, the hubs alone will probably sell for more than the complete wheelset. Stupid, but that's how it is - almost no one wants tubulars.)