Try this website https://www.uship.com/
You fill out the info and then carriers from all over the US will bid for your business. You can accept or decline any offer and there is no charge to use the service. Good luck.
Brokers are huge rip off and may or may not provide the agreed to service. I screwed around with several "national" agencies and finally gave up. Found a fully bonded & insured independent who beat the brokers prices by 40% and did everything right on time. Of course since mine was a shorty, it fit (barely) on a big trailer. A 40 footer is a different story.
I just got a quote to haul a bus from N GA to S GA, 4hr drive - $2k