If the gun looks something like this
please examine the underside of the barrels for proof marks. If Belgian, under no circumstances should you try to use the gun, with
any 10g load.
W. Richards guns were produced by many makers (Crescent in the U.S., Belgian, and some Birmingham) to confuse the unknowing, and were not of high quality even when new. If a side-lever, it likely dates to the 1880s and has Twist barrels.
If your desire is to make it a wall-hanger, 'parts guns' do appear on the auction sites and you might be able to harvest a stock.
