First there is no hurry. The Bendex website is a little confusing, oh I have
the Ford numbers but does no good, Bendex has no cross overs. This looks
like the run of the mill adjuster (left front). Previous owner took it for another
truck, I bought it that way. Problem is it has fine splines for the (S cam)
In all my wrenching for 60yrs all were course spline, the common ones. This
is for my tractor a 1950 F8 a real nice straight Texas truck. It stops on a dime
with only 3 brakes working (but the trailer got air,so) In time I will find one,
but so I ask that a lot of these were made into pickups so maybe someone
saved some big job stuff in their junk box.

its for this one the orange one sam

 

Slack adjusters come in 10, 18, and 32 splines. Do you know what you have? Aftermarket adjusters are almost a dime-a-dozen. Did you check out that Haldex adjuster, or are you trying to stay original?
Here's an example of what you can get for $25 and change, or maybe you want free: Beautiful set of triplets you have there.