I recommend rebuilding the master cylinder. You can do it yourself. A new (not NOS) master cylinder kit is fairly inexpensive. (Buy from a brake parts specialty company.)
I would also replace the brake shoe return springs. Over time they become weak. If the spring does not pull the brake shoes in, the front shoe will grab (when going forward.) I bought some new from Roberts for $7 each.
I would also replace the brake shoe return springs. Over time they become weak. If the spring does not pull the brake shoes in, the front shoe will grab (when going forward.) I bought some new from Roberts for $7 each.