I have an odd ball 3 speed with od out of an 86 swb c10. It's an np 883. Came factory with the Hurst shifter. It needs a rebuild new synchros and bearings. The pilot part of the input shaft is worn from riding in the bushing. What's the fix for this? New input shafts seem hard to come by and rest of the shaft seems ok. Is there any sleeves or anything maybe?

I'm not sure if it is available for your trans but probably is. A thing called a Speedi Sleeve. It comes in a kit with a pilot bearing/bushing just for that problem. I used one once. It worked fine. That thing is only working when you are in gear with the clutch disengaged. Check engine, bell housing and trans alignment. Otherwise find another input shaft and switch it out.

You might look into having the shaft metal-sprayed and turned.
I don't know what it might cost.

Will Willis

You could turn the shaft pilot down a bit and make a special pilot bushing for the back of your crank with matching inside diameter. Bastard setup for sure but would probably work fine.