It’s been a while since I saw one of those rear mounted metal side chutes. I remember them as being of pretty thin steel.
Unlike Norm, I’m no expert but if it was for my use I’d give it a rub down with abrasive to remove the surface rust and then clean it back with prepsol before a couple coats of antirust hizinc primer. I use the grey stuff and it’s good. I leave the grey to go off for a day or two before coating with the hizinc black. I’ve used the same process on tools such as shovels and hoes and it’s lasted well despite years of use.
They occasionally have a special on cases of the spray cans locally and while It’s not the cheapest it’s very durable and looks good over time.
