We shot it ourselves.
Remove your blank adapter from your M-16. Take one unfired blank cartridge and put it nose first into the barrel of the weapon (somewhat using the M-16 as an old-style grenade-launcher). Chamber another blank round into the M-16 and go hunting. When you see an armadillo, first the weapon. The pressure from the firing propels the blank that had been lodged in the end of the barrel at your target. Usually, out of an eight-member squad, you could count on two or three striking the armadillo and, if you were lucky, hitting it in a sensitive enough place to kill it ... usually the head.
Gut it, skin it, carve it up and either roast it over the fire or trade it for fish that you could get from the mechanics who always parked their M-88 recovery vehicle near an impoundment so that they could fish off the front of it.
Ahhh... the good old days ... when we were so young (and too stupid to know it).