Definitely get the extra six and a half fret.

I started with Neal Hellman's "Richard Farina Dulcimer Book" and Leo
Kretzner's "Dulcimer Fair". Both great books for chords as well as tunes
- especially if you have the albums. Neal released his book as a free
PDF some time ago. I can't find a current link on the web but I
shouldn't think Neal would mind if you sent me a PM.