Yes; the PAQ form could do with an update.
And yes; you would think that suppliers would be able to produce any or all "universal" codes for the stuff they are hoping to supply (sell).
Personally, I would reject any that don't or can't. Why? Because it's an indication that they may not be (or more likely, aren't) serious players ... therefore bringing any other declarations they make into doubt.
Yes; C11 had plunger rear suspension (as did 200 cc Ariel Colt) ... whilst C12 had swinging arm. PM sent.