47-55.1 Transmission seized

[Fred n' Ethel]

Hi folks. Had been watching the lube level for years. Barely needed topping off on occasion. Anyway, just took it out for a ride and while climbing the steepest grade in the county in 2nd, started loosing power/speed, moaned and groaned to a stop. I think the clutch began slipping at the end too. Managed to pry the truck uphill a bit with a fence post to get it in neutral to drag it home. All the linkage worked fine, no gears crossed so I pulled it out. There was hardly any oil in it The one gear is seized to its shaft. The bright sunlit area was evidently hot as it is bone dry, galled I suppose. How do you get those shafts out ? There is a lot of wear throughout, are they worth rebuilding ? Any used ones available ?
Thanks,
F&E