Sadly I doubt if we will ever see The Quest. Cannell was the biggest champion of getting his shows released, and with him passing away several years ago not much has been done with the series his company owns. Most of his shows from the 1980's have already been released on DVD, except for I...
I remember "Falcon's Gold" (aka "Robbers of the Sacred Mountain") with Simon MacCorkindale, but I don't have a copy and I have no idea who owns it.
Ownership of The Quest remains with Cannell Entertainment, I think I have almost all of the episodes..