"My dear people!"

Today I received a Dutch Linguaphone Course English.
On two records it says that 'Prof. J.R.R. Tolkien' speaks on it.
Also in the booklets Tolkien's name is mentioned as a participant.
My question is: how much would this course be worth? If it is worth enough, I could insure it...
I am not going to sell it, perhaps if I find another one and then I'll mention it here again.

Hoping you can help me

Onónion

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