S/N on an Inglis BHP is on the chamber of the barrel(should be visible in the ejection port, the slide and the frame. No such thing as an Inglis without a S/N. CF logistics types would have excrement fits.
You sure it's actually a Browning and not some clone?
"...the bluebook..." Will only give you averages from all over the U.S. with no regard for local supply and demand. The assorted auction sites while a bit, um, over priced and usually not local either will be better.
Spelling and grammar count!