Don’t think it would be to directly pressurise the priming circuit instead of the Ki – Gass, because of the lack of control. Its a small pump but it moves a significant volume. The Anson operating manual gives the required number of pumps on the Ki – Gass required dependant upon the ambient temperature when starting, which I doubt you would control with the electric pump alone.

Actually this is something that is not as big a problem as you might think. On many fuel injected engines you prime the engine using the fuel pump (electric) and then shut off the fuel pump and close the mixture again. This way the engine is basically flooded, but as you crank the engine and air is drawn through it the mixture progressively leans until it reaches its optimum point at which the engine fires. You then open the mixture to keep it running. I’m sure I’ve read about this same technique being used on radials (I’ve only used it on flat-fours and -sixes). On fuel injected Pipers with the optional priming system installed there is a graph in the manual that also uses ambient temperature and gives you the number of seconds that you need to prime, quite similar to the number of pump strokes in your paperwork.