Found the kingpins for my 1969 4x4 F100 at http://www.greensalescompany.com/default.asp but they only had 3 of the 4 and found the last one at a ford dealership in SC. The part# C8TZ-3B289-B for the kingpin. These are hard to find! The people at Green sales company where very helpful and told me the parts# and found the other kingpin SC with there parts locator.
I didn't no if there was any left out there to be had.
When you rebuild a kingpin 4x4 axle what you're doing is replacing the bearings, cups, seals and springs or re-shimming for the proper clearance and spindle centerline.
I hope you didn't buy four actual kingpins. You shouldn't need them unless they are damaged.
Never worked on a KP Dana 44, but have rebuilt and restored several different manuf 4x4 front axles from the 50's and all the parts are either off the shelf items from a bearing house or stuff you make yourself with a lathe, mill and broaches.