1K ammo? That's two 500 count bricks of .22LR Remington Thunderbolt, which I can buy, with change left over, with two Jacksons.

I could see unusual if it were, say, 1000 .50BMG, but not (yet) illegal.

This could be some lonewolf under the radar flier. Or false flag work, to yet again stab at the 2nd. Not enough data.