In that condition, it would give me pause too. The 26-1 is one of only two commemoratives that I can think of that have unique model numbers (if there are others please jump in and enlighten me). Other commemoratives are simply versions of an existing model - maybe with an engineering change number, but still an existing model, i.e. The Model 25-3.
There are no "plain" model 26's, the only way you get a gun marked Model 26 is with the commemorative markings.
The other that I can think of, is even more unique and that is the model 544. You can buy other N-frames in .45 Colt (other than the 26), but there are no other N-frames chambered in .44-40.
Any other unique model number commemoratives?
Adios,
Pizza Bob
ETA: My bad. There was, of course, a model 26 that was not a commemorative. It was the model of 1950 in .45 ACP with the lightweight profile barrel. So the 544 stands alone as the only unique model number commemorative?