Apple. iUP and direct purchase for T-Mobile network.

I was able to get on order in via mobile app and a couple more via web. It took 30min of refreshing; longer than the usual 5min.

Good luck

Have you considered EPax? They sometimes offer refurbs at price points that may fit your budget.

Not sure if all their components are US sourced, but they are US based and offer real customer support.

Maybe you have too much squish?