Norton 16H 1936

I've never seen any for sale. They were superseded by rubber hoses on the WD 16H and I don't believe that the rigid pipe reappeared after the war.

They're straightforward enough to make using soft copper pipe but unless you have access to a lathe, you may have to recuperate the lower nipple from your old feed pipe.

Norton used a 5/16" union at the oil tank, with 5/16" pipe but a 1/4" BSP union at the crankcase. They achieved this by using a nipple which inserts into the pipe rather than over the outside and from memory a slightly larger opening in the nut. I've never seen these parts for sale.

My exit pipe from the oil tank has a copper crush washer so it will both line up with the pipe and seal at the tank.