A check of on line auctions will give you an idea if any have sold lately. Blue Book of Gun Values has information on what the various conditions might bring(100% to 50%) but, it is dated as soon as it is published. Check local gun shops and pawn shops also. Without a detailed description or photos, there is no real way to put a value on it.
100-600 depending on specifics
You call Sig Sauer
You have to call SIG
The SIG Sauer P226 has been modified for suppessor installation.
You will have to call SIG.
Recommend you call SIG directly.
20-400 usd
it is definitely the sig sauer sp2022
Best left to a trained armorer
Prices vary by region, but, you are in the 500 USD range.
SiG P229 in 357
Sig Sauer P229 and P239 chambered in .40 S&W. Here's the press release from Sig.