Send the information and pic's to Colt. I know they are going thru bankruptcy but hopefully they'll respond. 10 years ago someone we knew purchased an old Colt at a gunshow. Took it to his local GS for a valuation. GS told him what I mentioned above, and to be patient.
Patience wasn't a virtue.
Before he received a response back, he sold the revolver for a $50.00 profit.
True story. Colt got back with him 8 weeks later. The revolver he had in hand, was specifically made for/issued to/and carried by Sheriff WW Bat Masterson.
They placed the value between 8 - 10K
He sold it for $250.00
Sorry I babbled and know it didn't answer your question, but please take your time.
He is your friend defender your dog. Be worthy of such devotion