You maybe able to remove starter, disassemble, clean up, check brushes, or find replacement brushes. Lube with white grease, and then reinstall. I did this to my IH3444 BD154 engine starter. The problem was the solenoid contact buttons were toasted. I turned them 180 degrees, reinstalled them and all had been working fine since 2006.
What part of country do you live in I ask that because there is a company in California that can make you a Denso style gear reducted starter to replace yours, in most cases you have to send them your drive in housing and clutch to be exact match depending where your located I can help you find a dealer to help you I can order from them but I live in Georgia.