The frame is coated with (Gray) Nason SelectSeal 422-28 2k Urethane Sealer over the anti-rust Nason 491-17 self etch primer. Then I just spray the base with Model T black. This is how so many NOS pumps I have found were done. I spray anything that sticks out like the light switch, pump hook etc. with Omni Texaco Silver enamel. They most likely made these pumps as fast as they could just like the Ford Model T's. They probably would not have wasted time masking things off like the base.
In the end no one knows but the owner.
Travis
Topeka, Kansas