Boris,
The San Juan Parlor Cars are accounted for. The "Alamosa" is in Durango. The "Durango" is at Knott's along with the chopped up "Chama". We'd HAVE to go to D&S or Knott's to have a chance of pulling this off.
I think the car body Earl (or was it Coker)is referring to, is a baggage car. But there is no proof it is there, just legend
The two Parlor Cars from the Shavano Train were traded or sold to a RR in Mexico in the early 1940's (1942 comes to mind) and are most likely gone. But they weren't for the San Juan anyway.
Playing the Devil's Advocate on the Coaches, The D&S and Knott's both rely on those Vestibule Coaches, why would they get rid of one or two to the C&TS? or Trade for a converted box car in return?
Kevin