The AR-7 was originally designed for the civilian market by Armalite. Earlier, they designed a bolt action 22 Hornet for the U S Air Force. The action and barrel fitted into a fiberglass stock, similiar to the storage in the current AR-7. I believe Armalite designation for the Air Force model was AR-5.
The AR-5 was given the military designation MA-1 and adopted as military standard, but was never placed into production. The Air Force appearantly decided their existing H&R built M-4 take down 22 Hornets and the M-6 22 Hornet/410 bore over & under were adequate for their needs.
With more reliable aircraft, improved search and rescue techniques and world wide communications capabilities, survival "long arms" generally are no longer carried in military survival kits.
After Charter Arms gave up the ghost, a Florida company named, as I recall, Survival Arms built the AR-7 for a while.
I have one of the old Armalite versions. While a neat and handy rifle, I find it's not as reliable as I like. It seems very sensitive to magazine feed lip configuration and will, on occasion, fail to align the round with the chamber.
Accuracy is reasonable, considering its weight and expected use. The integrel peep sight is handy, altho a scope makes it easier on my tired old eyes. Overall, I prefer my modified Savage 24C Woodsloafer Special to the AR-7 or M-6 as a "survival" woods-carry firearm.