Electric fuel pump through Mechanical Pump

[Igrantum]

Alright, I have a 1980 Datsun 210 and a coworker of mine said this is a good place to come for my car even though it isn't the 240sx.

The car has a 1.2l carbureted engine, with a 32/36v weber carburetor on it. I don't know a lot about carburetors but I know the engine runs and that's not the issue.

I have a failed mechanical pump on the car and there is no electric pump. I cannot find a replacement part anywhere, auto stores, rock auto, Nissan dealership, and I didn't want to buy it off eBay.

I was thinking about installing a new electrical pump, but was wondering if I need to do anything apart from wiring it up to the ignition, getting a fuel regulator (I need 3psi rather than the 4-7 most I've seen have), and installing a filter before the pump.

So:
1. Is it okay to leave the electric pump running through the mechanical pump all the time?
2. Do I need anything more than the filter, pump, and regulator?
3. Anything I missed or overlooked?

Thanks