Check this guy out for EV spec Thiele. I've bought two of them from him, black and blue color. The blue one "almost" matched my LSC head. Kinda weird covering, but looks to be able to hold up much better than tolex.
I have a "real" Mesa Thiel and they sound IMO just as good or better. I run 2 very old EVM12L in the new ones.
I have NO association with these guys. I just liked the product and I know the Thiele cabinet is one a lot of people want, including myself.
http://cgi.ebay.com/EVM12L-designed-thiele-cabinet-extension-cabinet_W0QQitemZ270170401984QQihZ017QQcategoryZ121165QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
jenks