Commodore appears to be a uniquely UK distributor brand name. I've seen it reported that Paul Day suggested it was a brand name used by Rosetti. I have a few Rosetti catalogs but I haven't been able to locate them up to this point. However, I did find a group of 70's Bell catalogs and a solidbody Commodore N 180 bass is offered from 1970 through 1975. It's gone in the 1976 catalog. So, if Rosetti used the brand name, it wasn't exclusive to them.
I've seen the Commodore Aria/Matsumoku speculation also and I think there is definitely something to it. In the 1974-75 Bell catalog a second hollowbody Commodore N 40 bass is offered that is identical to a 1971 Aria 5120. When comparing the N 40 to the 1974 version of the Aria 5120, they are virtually identical except for the pickups.
I've seen enough evidence on the web to convince me that hollowbody Commodore, Aria and Univox instruments were being sourced from the same company. I'm less sure about the solidbody instruments. I haven't found an Aria counterpart for the Commodore N 180 bass offered by Bell in the early 1970's.
Here's another thread about a Commodore Jag copy that might interest you:
Statistics: Posted by VintAxe — Mon Jan 17, 2011 1:10 pm
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