JMHO;
By the mid 80's (35 years ago) EFI was becoming the norm and we were seeing fewer carbureted motors coming from auto makers. By the mid to late 90's (over 20 years ago) EFI became a Federal mandate and carburetors were deemed obsolete. Soon after auto makers sold off their carburetor related stock to aftermarket suppliers and without the demand manufacturing support dwindled.

Today, most aftermarket parts that support our older/classic cars are manufactured offshore. Unfortunately, without high demand for the parts most manufacturing standards are far less than they used to be. In the case of mechanical fuel pumps for carburetors the demand is low. Usually the offshore fuel pump housings and internal parts are copied closely and in most cases a visual inspection shows little differences. Assembly of the parts is often the failure point, in most cases the assembling entity has no understanding of the use of the product being assembled. Usually, the testing and quality control of these products is simple a look and feel. Meaning, the part looks complete and maybe the pump’s actuation lever is pushed to see if air comes out.

I have seen these mechanical fuel pumps output far higher pressures than any carburetor can tolerate.

Again JMHO, but in todays world, I would NOT run a carburetor without a fuel pressure regulator. PERIOD…