Cheers guys, thinking about a bit of restro and linenbacked.....
A personal decision. Do it only if it increases your enjoyment of the poster. It won't increase the value, and certainly not by the amount backing would cost.
doesn't look to me like it needs backing. I've only seen one sell and that was a while ago at just over $300. I reckon in good shape it's rare and would be worth closer to $1000 now.
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