Re: Rebuild head, or replace, and with what?
Check which model of Groco it is. My Catalina 25 came with a GE and upgrading the parts to a use their modern pump was close to the price of a new head.
I put a Raritan PHC in my Catalina and again in my Pearson. They have a great reputation and have worked well for me so far. They are in the $200-$250 price range.
I'm no longer participating on SailNet.