Hard for a porty hack to play the 15a/20a outlet game without knowing the total number of amps that their cords require.
You can't determine what difference using a vac with 13a as opposed to one using 10a will be until you know how many amps your pump needs and get a total for the cord.
Assuming your below 20a in total of course, the only difference will be knowing whether or not you MUST always source a 20a circuit or not, and also how often you can get away with using the more abundant 15a circuits.
So how many amps does your pump pull?