...now's the time...
I'd take this opportunity to learn how to re-build it. If nothing else,you could clean it up,check out the armature on a 'growler' at Auto Zone and replace the brushes. You could also check the solenoid and all the wiring and contacts. That alone would probably make it a 'brand-new' starter. Found out that you can turn the contacts and have a 'new' surface to play with. Remember...this OD iron was made to be taken care of by barely trained 'kids', in the field,in combat,under duress and with a minimum of tools. Learn about it while you have a chance to do so....IMO