i got one of these from Xcase for mine...got it quick!
http://cgi.ebay.com/XCase-Fender-Bas...efaultDomain_0
just ebay search for 'fender 300 pro case'
and with all the knobs and sliders, a case is a must!...
AND you definately want the 'lift off" style case.. as big and awkward as that head is, you DONT wanna have to lower it into a case.
If ya talk to XCase, they will probably also make you one with wheels or a dolly if ya want.