FYI - "NWTF: = National Wild Turkey Foundation", and FWIW, such markings generally devalue any firearm so marked for various customers, except for members of the particular association (NWTF in this case).
Firearms so stamped/marked usually change hands for about 20% less then an otherweise identical, but unstamped, specimen in the same overall condition because most buyers would prefer their firearm not be so marked.
AFAIK there is NO collector market for BPS'.
A BPS in excellent condition will usually sell for $400-$450- which would put a fair market value of a NWTF BPS at $375-$400, +/- IMHO.
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