wrote

A quart of prime would be six or eight times as much as is needed
to preoil the engine. My little hand-pump on my A-65 does it with ten .
75 cubic-inch strokes, for 7.5 cu. in. total. A larger engine might
take 10 or 12 cubic inches.

Someone on the RV forum mentioned making an accumulator out of a
air-conditioning freon can. That, plus a couple valves and plumbing would
be pretty darn light.

One thing to keep in mind, is that the pre oiler will not do anything to
lubricate the camshaft, one of the parts that takes the most wear on dry
start-up.

If this is a non certified application, you could split the cases and add a
spray bar to help the cam.
--
Jim in NC