Well, this is what a Color Computer 2 looks like when it boots up:



And "VER" returns:

?SN ERROR

(Happen to have MESS with a CoCo ROM handy.) So, yeah, almost certainly a 1000EX/HX. Or a *really* impressive casemod. (A CoCo 2 would be hard to fit a Mini-ITX motherboard into, let alone the guts of any 80's PC clone.)