I would watch these sites.

http://www.auctionarms.com/

http://www.gunbroker.net/

http://www.gunsamerica.com/

They currently do not have any listed that I could find. But I would monitor them on a weekly basis. Good luck

Edited to add: Gunbroker has sold 14 of them in the last 90 days. So you should be able to find one their sooner or later. And they averaged right around $300.