I have one. I am second owner and it has always been shedded. Repainted once and new web once. I really like the spreader since it does a good job in strawy cow manure. Cannot get the same triple beater on today's spreaders.
I take it that the wood is all shot on yours and the metal is bad too if it has been setting outside since the 1970's.
It probably only has a home made trailer wood hauler value if the manure spreading mechanisms are rusted out.