You're in luck. Here's a DVD-N501 on eBay which I believe is a short 3 day listing thus it has no bidders yet, is cheap atm, and ends in only a day and half!
http://cgi.ebay.com/ws/eBayISAPI.dl...MEWA:IT&viewitem=&item=320069133273&rd=1&rd=1
Yes you got a good deal in my opinion. Now you must get Tempest 3000 priority 1!