Hey �Mike,
You can make your own metal spacer with a few basic tools. � Get a small chunk of 1/8" to 3/16" common steel. �Use your new pump base as a template. �Draw the shape with a fine point sharpie pen. �With a grinder, vise, safety glasses and a cutting wheel, cut the piece to shape. �Slip on a grinding wheel and grind it down to the precise shape. �Drill the two mounting holes. polish it up with some 220 sand paper and waa laa, home made spacer.
I made mine this way. �Same reason as you. �No need to spend that kind of money for a small piece of steel. �You will also feel a sense of satisfaction from making your own part.
I am no expert on when a Willys needs a spacer. �Rocketeer and others here will know for sure, but I believe the CJ3A and M38 pump with the vacuum function require a spacer. �If you don't use the dual action pump, then no spacer is required.
One reason for the spacer is that it reduces the pump pressure. �Another reason I have found is that it will fit better tucked in behind the front engine mount plate. �Good luck, and welcome to the site.
Tim �