I would try to get Nic Volquartsen to write up a letter stating that this is one of the 100 they built. It would give validity to it's rarity, and if only 100 of these exist in the entire world, it is exceedingly rare.
If it is 1 of 100 built by Volquartsen this revolver would appeal to fans of Volquartsen, Smith & Wesson, and any collector of rare revolvers. Volquartsen has a reputation for excellence. The only reason this wouldn't be "collectable" is that there are not enough in existence for people to collect them. If they ask for you to pay for this service, do it because it is worth it.