We recommend "Then & Now Automotive" for fuel pump kits.
If you are going to buy a "new" pump, far better to buy a new old stock unit and then rebuild it with a kit from T & N. That way you have the best of both worlds; castings with no issue, and new internals.
We have tested some of the new name-brand (old American brand, now made elsewhere) fuel pumps at waaaaaaaaaaaaaaaaaaaaaaay more than 10 psi. Good luck on getting any carb to hold that pressure. And you might get one with 4 psi. Quality control?????
Jon.