Quite often, shopping on Ebay will give you the option to ‘Make An Offer’ on items which I do when buying more than one. Last year I picked up a few of these same pumps for about $5 each with free shipping. So far I’ve used them on a Honda gen set and a rider mower with no problems.
I used one for a 1953-54 Evinrude 15 HP this past fall. Tested good in the driveway and first run on the boat. Seems like a good option for some applications. https://vimeo.com/362318925