Scott:
If I recall correctly, Jim Maloney (Reds) and Don Wilson (Astros) also pitched back to back no-hitters in the late '60s. I was just a little kid, but that's how I think I remember it. I attended the Maloney no-no, and then I believe Wilson came right back and pitched his the following evening.
Both games were at Crosley Field... at least that's how I am remembering it from 40+ years ago.
Anyway... just curious as to whether you have either of those Tickets? I figured if anyone does, it would be you! I wish I had the knowledge way back then to save mine, but it is long-gone