The Monkees model Gretsch guitar (a 6123) was available from 66 thru 68. It had to be ordered, by the music store (which means Gretsch made them by order) and was discontinued due to pathetic sales...The Monkees, at that time did not even play on their own albums. The 6123 had become popular because of George Harrison's frequent use of the Tennessean, but George would never endorse the model with Gretsch. So they settled on the Monkees, who actually played more than one Gretsch model. Best guess is that 200 Monkees model Gretsch guitars were produced. Today, the Gretsch Monkees Signature Guitar is a highly sought after collectible. Who knew. I'm guessing it was loaned to, or part of the cache of guitars the studio has where Glen recorded GOTC.