There are two different numbers involved here. First, it was clear that you may be struggling with other heirs in order to obtain this gun. My estimate of $500 was aimed as a fair price, but not the top of the mark to save you some money. You do not want a high auction value for your purposes and so high valuation is against your best interest. The engraving is not proven to be factory, so should be considered New York style which was done outside the factory. Without the engraving, you will find guns selling out there for under $400 and non-factory engraved guns will not command that much more money.
I would bow out of this debate on the Forum and go out to Gunbroker and do a search of recently sold Model 1, 2nd Issue revolvers, comparing condition to come up with actual selling prices, which is not the same a valuation.
You can sign in or sign-up to gain access to the sold items in Gunbroker. Once signed in, go to "Advanced" by the search box. There will be two tabs, click on the Completed Auctions. Enter
Wesson Model 1, 2nd in the search box and you will find 8 that have sold in the last 30 days, one of them is mine that sold for $265 in full working order. When you find them, make sure that you use the examples that have bids listed. If you cannot make this work, send me a private message and I can send you those 8 guns. Also, check out this entry with item number: 925876192. It is below and it DID NOT sell for their asking price of $399.