Already spent the budget on other items. An AR would be a nice thing to have just in case.
What is a good “hardened” version — caliber, etc. Caliber that is readily available probably in nato. Want something that is robust outdoors — rain, dirt, etc.
Too subjective. Someone I know has an ARmalite they like. Others have Colts, S&W, and many others. If you can find some range that has a variety of brands, that would be the way to try some out and decide. Obviously the 5.56/.223 is probably the most common easy to obtain round. Good luck. And, some of the offerings are NOT that expensive.
“What is a good “hardened” version..,”
Rock River Arms 5.56...Swiss watch of AR’s,
Get one from Palmetto State Armory. You cannot beat the quality for the price. About $300 for the kit and then about $50 for the Lower receiver and another $50 for the LPK. Buy several. I know I will come this fall.
Rifle Kits:
https://palmettostatearmory.com/ar-15/rifle-kits.html?dir=asc&order=price
Pistol Kits:
https://palmettostatearmory.com/ar-15/pistol-kits.html?dir=asc&order=price
5.56mm. Don’t listen to the “poodle shooter” claims. It’s a nearly ideal close quarters rifle cartridge.
Get an AK 47 clone in 7.62. Very reliable and very easy to field strip and clean.