[G_Edmonds]

I think most people use an early 70's corvette brake master cylinder.
I recently changed up my fuel system. The fuel pick-up and sender looked just like yours. I just cleaned up the float, cut off the rusty fuel tube and added another. (Actually put an in tank pump in it.) I was surprised that the tank was very clean when I opened it up. The tank is not sourced from another vehicle so you would have to find something that fits or have one made if yours is bad. Just buy some cork gasket material and cut out a sender seal. A carburetor rebuild kit for your model Holley should have all the seals you need.
Good luck.
-Greg