When was a Model 250 J Stevens A and T Co with no patent date serial number 2803 made and where can you find a forearm and stock?

Well, not sure about the 'J' suffix, but the Stevens Model 250 was a sidelock double shotgun with external hammers. Made c.1877-1890 (or so). Stocks would absolutely have to be made from blanks. If you need the entire forend assembly, understand the forend iron would probably have to be cast and machined... UNLESS you got lucky enough to find another gun for parts. sales@countrygunsmith.net