I just found this seller on ebay in Texas today and snagged one. He has used 20lb aluminum co2 tanks at a decent price, and he is claiming they will come with a new hydro test.
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http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170414640293
No affiliation
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170414640293