You can check w/ Mossberg, or with havlinsales at their website- but the bad news is that a complete bolt will cost you about half of the value of the rifle, AND it should be fitted by a gunsmith. Sorry-
100-300 or so
100-300 or so
100-500 USD or so
The Mossberg 810A was produced in the 1980s, and the serial number 639582 suggests it was manufactured during that time. To determine the exact year of production, you may need to contact Mossberg directly or consult historical production records, as specific serial number databases for older models may be limited.
Your westernfield model 765 was made for montgomery wards(westernfield) by the mossberg arms company.The model 765 is the mossberg model 810A.
Mossberg Model 810 bolt action made 1970-1979. According to gun traders guide-also two variances-detachable magazine 70-75, internal magazine w\hinged floorplate 72-up