I have had trouble with both new mechanical & electric pumps.
The only mechanical pump sold as a spare part in Oz is a generic pump that looks the same, but has a longer arm, making it semi suitable for a large range of classic English cars . Unless set up properly with the right spacers between it & the block, it will pump up to 4PSI on our engines, & give serious flooding.
Incidentally for anyone interested, the diaphragm in the lift pump kit for my 1950 Fordson major tractor fits the 7. The kits cost just A$13.
Most electric pumps sold here also have too high pressure, & will cause flooding. I currently have an electric 2.5 PSI pump made in New Zealand, which is "ALMOST" good. With it the 7 [with SUs] will perform faultlessly for a month or three, then give intermittent minor flooding for a while. I have been unable completely cure this, but find it the best compromise. UK Phil is having a similar problem.
I have tried pressure regulating valves with both types of pumps, & find then a total pain in the ass. They have to be so restricted to work on our cars that the slightest bit of silt in the fuel will shut the flow completely. This is surprising as we used the things set at 2 PSI on Webber carb Formula !s & Formula 2s back in the 60s, with complete reliability.
Don't know if this helps, but may be useful background for your decision.
Hasbeen