Most major outlets get them, but they're in such high demand right now they fly off the shelves. Sportsman's Warehouse gets them here, but they've told me they come in on Monday and are gone Tuesday morning. Just a matter of continuous shopping and grabbing it if you find one.
And so far, yes, it only comes in .45. That was the original design and it's a pretty new gun. I think I've heard of plans of a 9 down the road, but not confirmed and no ETA if it is.
I've only had the chance to fondle, no firing, but they seem super sweet to me. Almost everything I've heard is positive (there are always a few nay-sayers) and I've heard the recoil is surprisingly manageable for a .45 that small.
"I swear by my life, and my love of it, that I will never live for the sake of another man, nor ask another man to live for mine."