Do you have a Groco, bronze full flow 90 degree fitting that is a 3/4 male thread with a 5/8 barbed end?
We do not carry that exact size but you can use the 1/2" 90° Bronze Pipe to Hose Adaptors and a bushing to make this work for you.
Where’s a good place to buy bronze pipe (bilge plumping) and bronze 1.5" round stock (centerboard).
Bronze pipe or tube is rare. It has speciaized uses and is expensive.
Morgan Bronze and National Bronze and Metals handles bronze pipe.