Well, I have one ( I think Rick made Rich more than one). I bought it on June 2009 to Maverick-Music, and still is in my hands ( really I will never sell it ). Mine havent back pannel, tomorrow will see serial number ( is around WC484 not sure but very similar ).
I know mine was sometimes on Ebay and none offers on it. Finally they relist sometimes and I did an offer and they accept, I think this is the reason you see the same amplier sometimes on Ebay, Maverick-Music also keep in his list of Gbase for a long time.
I can´t remind but I think I read thet Rich had unless two of this heads.
Sorry for my english. If you need pictures or something else let me know
Regards from Spain