eBay: is this shag print authentic?

Hey All,

I've seen this auction on Ebay before and always questioned its authenticity. I'm no Shag expert, but I haven't seen/heard of this serigraph before. Kinda think of it, I've never seen/heard about the painting before. It looks real. I just don't remember the show it was from.

http://cgi.ebay.com/Shag-Rose-Seidlers-House-HUGE-Serigraph-MINT-Condition_W0QQitemZ120318946372QQcmdZViewItem?hash=item120318946372&_trkparms=72%3A1207%7C39%3A1%7C66%3A2%7C65%3A12%7C240%3A1318&_trksid=p3286.c0.m14

Here's the description on ebay:
"This is Shag's long sold out and very RARE 8 color serigraph print entitled ROSE SEIDLER'S HOUSE. The print is numbered # 64 of an edition of 195. The print measures approximately 21" x 35". It is hand signed and numbered by Shag. The original Certificate of Authenticity is included. This print has been safely stored since purchase, never framed or displayed and is in perfect MINT condition. I am thinning out my extensive Shag collection as I have realized I have far more than I could ever display. Please email any questions. I ship quickly and carefully via insured USPS priority mail. International shipping is $40.00."

Here's the picture of of the print:

http://www.outregallery.com/browse.aspx?Category=59

Thanks for clarifying. I guess it is very rare. Sweet.