Hi everyone, sorry if ive posted this in the incorrect area of the forum

Im looking for a little advise if i may?
A good friend of my family, has asked if i would sell a few bits for him which he has found in his loft from his time as a mechanic in the RAF.

Most bits are mainly fairly straight forward to sell, however im struggling with the following, and believe it to be a fairly "rare" Air Publication:

AP No. 1374 Handbook: Aero Engine Magnetos - 1936.

I have found very little relating to it online, and cant find one that is either for sale (or has sold) to get a idea of value.
I hate to be one of those "whats it worth" posts, but im struggling and could do with a pointer if at all possible.

Any thoughts greatly appreciated.
kind regards
Ed

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