After searching for three years, this is what I’ve learned. Only a hardtop from your years (or recent years to your boat) will fit. Ones from a 24’ boat or others won’t fit without a lot of fabrication and even then, the aluminum piping is probably shot.
Don’t want to be discouraging, but I’ve called every boat for sale within reason and no one wants to sell a hardtop.
The main problem with Seafarers is that hardtops were optional and everyone who doesn’t have one wants one.
I’m having one made for mine. I’ve given up looking.