If a coin dealer offered you $20 for the note, he either misunderstood what you have, or was attempting to rip you off.
Would you be able to post a scan of your note please?
If the note is what you say it is, it would have an Uncirculated value of approximately $1,000. In F/VF, you can expect somewhat less than that, perhaps around $350.
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BWJM, F.O.N.A.
Life Member of CPMS, RCNA, ONA, ANA, IBNS, WCS.
President, IBNS Ontario Chapter.
Treasurer, Waterloo Coin Society.
Show Chair, Cambridge Coin Show.
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