That part number 388684 is relatively common for the fuel pumps, don’t think it is unique to the 9.5hp. Unfortunately, this simple fuel pump comes in many different configurations. The pressure port mounting could be horizontal or vertical, and the fuel outlet nipple could be found in three different directions. Most of these pumps have an arrow, or an “up” indicator that dictates how the fuel pump must be mounted to work properly also. The pictures on the parts diagrams are not always accurate, always best to compare the pumps looking to them side by side.
Some of these part numbers are different because they are “kits” containing more pieces than just the fuel pump, the actual fuel pumps might be the same though. I would say that any of the small OMC pumps that have the same pressure screw mounting orientation, the same fuel outlet nipple direction, with the UP/arrow facing in the same direction will work for you. Look for a used one, I realize the price of new OEM pumps is ridiculous.
I would skip the cheesy amazon/chinese replacements, they usually are not even worth the price of shipping.