Vietnam War Paratrooper Boots?

I got these years ago when I was on vacation in in New Mexico or Arizona. I was in the market for some new boots and I found these. The seller said that they were a private purchase that were converted with the side zippers or something like that, I really can't remember. Anyway they've gotten to small for me and have been sitting in my closet for a few years now and I still really don't know if the story is true. Anyone familiar with them?

Yep they are PX purchase boots that have had a zipper added. They could just as well be some legs boots as to be Airborne. No way to tell for sure.
Sarge