Well in the aviation world, mechanical pumps are STILL THE STANDARD, with electric pumps as a backup. All they are is a lever, diaphragm, check valve and some springs, the electric pumps have a lot more to fail and are more susceptible to corrosion due to the crap they put in as additives in gas now days, alcohol is even worse. I would just get a diaphragm kit for a mechanical pump as a spare part and run it. But I am old school and in my world a failure = potential loss of life.