We cant make more of them easily.
Fairchild Republic went outta business in the late 80s, at least as a functioning aircraft manufacturer.
The old Republic factory in Farmingdale was an abandoned hulk the last time I was there 25 years ago.
The engineers who designed the A10 lost their jobs, left for parts unknown, and the only company making money on it is Boeing with the rewinging contract.
Maybe the air force could outsource it from China.
The Israeli company Elbit Systems is the current owner of what remains of Fairchild Republic. I doubt that there is any A10 tooling included.