Conspiracy Theory Mystery Cache

I recently received a very strange letter from a friend. I don’t know why he didn’t just send an e-mail. Heck, I didn't realize that he even knew what a postage stamp is.

Anyway, it sounds like he's been reading too many spy novels lately. I tried to ask him about it, but I can’t seem to contact him. Maybe there’s really something to this? It wouldn't be the first time he went off on some paranoid wild goose chase.

Here’s the letter:

Sorry for the poor scan.

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