Tanks, fighter jets and military helicopters. Nations sell this to each other all the time.

Weapons probably get transferred a lot but that won't fit my story, as the goods will be eventually stolen, and thieves should be just thieves, not mass murderers.

You don't ecessarily have to use these for mass murdering. A tank would do wonders if you wish to crack a bank vault open. No shots needed, use it as a ram and then as an escape vehicle/decoy, Pay Day: the Heist style.

In the US civillians can have tanks. Arnold Schwaznegger has one and he famously lets you smash things with it for a fee. I suppose in the process of buying a tank from the armed forces you need to fetch it in a heavily guarded depot at the very least.

Tanks, fighter jets and military helicopters. Nations sell these to each other all the time.

Weapons probably get transferred a lot but that won't fit my story, as the goods will be eventually stolen, and thieves should be just thieves, not mass murderers.

You don't necessarily have to use these for mass murdering. A tank would do wonders if you wish to crack a bank vault open. No shots needed, use it as a ram and then as an escape vehicle/decoy, Pay Day: the Heist style.

In the US civilians can have tanks. Arnold Schwarzenegger has one and he famously lets you smash things with it for a fee. I suppose in the process of buying a tank from the armed forces you need to fetch it in a heavily guarded depot at the very least.