[Arran]

It's possible that they used to be sales samples, you see that with some of the shoes that end up in Winners/T.J Maxx stores. The company representative would travel from store to store with a samples to show prospective dealers what each model was like before they would put an order in. Since they are usually early or even pre production they are often somewhat different then the full production models, see if there are any differences in the part and circuitry chosen or the cabinet from the usual model 45Cs.
Regards
Arran