Bradley frames from Franklin start at $1020. You ought to be able to build one up for $1000 with inexpensive components, if that's what you really want to do. Of course, if you want as many as possible of your components USA-made as well, you'll be spending quite a bit more. You could do wheels, hubs and seatpost from American Classic - I don't know about anything else.
I honestly don't know anyone who rides a Franklin frame, but they've been in business quite a long time and have a good reputation. American Classic is good stuff, though the only components of theirs I have are from the 1980s.
ETA: Here's a list someone made up: https://joecruz.wordpress.com/usa-made-cycling-gear/