via
The Bob Moog Foundation where you'll find the full post.

"My custom dual-manual Moog keyboard controller was built in 1974 along with two System 55 cabinets containing a host of Moog modules. I had been doing clinics in the US and Europe for the Moog company, was hanging out with Bob a lot, and had just joined Todd Rundgren’s Utopiathat summer. The big system was put together for me to perform with on tours. The keyboard was designed to my specifications: two keyboard manuals, pitchbend and mod wheels, a mixer section with four faders, an effects loop, VU meter, and sockets for a Ribbon Controller and standalone Sample/Hold module. Bob himself worked on the mixer circuit design, and also handcrafted aluminum edge protectors for the 55 cabinets to help with wear-and-tear on the road!"
Update: additional pics and the official press release:
"Synthesist Roger Powell Donates a Piece of History to the Bob Moog Foundation
Asheville, NC - November 14, 2012 – In celebration of its recent six-year anniversary, the non-profit Bob Moog Foundation is pleased to announce a generous donation from American synthesist Roger Powell: a dual-manual keyboard that Moog Music custom built for him in 1974. The keyboard, which Powell acquired shortly after joining Todd Rundgren’s Utopia, was part of a synthesizer comprising two Moog System 55 cabinets housing a host of modules.

'The keyboard was designed to my specifications,' says Powell. 'Bob himself worked on the mixer circuit design.” Powell had been doing clinics for Moog Music in the U.S. and Europe, sometimes with Bob Moog when the system was assembled for touring with Utopia.
Like a lot of Moog gear, Powell’s keyboard comes with a fascinating story:

'After the first evening of a two-night booking in Cleveland, the custom keyboard was stolen from the stage. Strangely, the modular system cabinets were left untouched. My guess is that the thief believed the keyboard itself to be playable, as it resembled a two-manual organ. A few years later, the System 55s were destroyed in a warehouse fire, thus removing all remnants of the original system.
'In 2002, much to my surprise, the missing keyboard was listed on eBay. The person offering the keyboard had no idea it had been stolen and was not the thief. (He was younger than the age of the keyboard.) I was able to negotiate its return and have held onto it since, hoping to refurbish it but never completing that project.
'After Bob’s demise and the creation of the Bob Moog Foundation, it occurred to me that the custom keyboard deserved to be in a place where it can serve as my personal tribute to my dear friend Bob Moog. Bob and I spent some very happy times together; I will always remember laughing a lot with him, as we both shared an acerbic, wisecracking sense of humor.'
The Bob Moog Foundation is honored to accept Powell’s donation, and we look forward to restoring the keyboard to its original condition. Our goal is to display it publicly so that, in Powell’s words, 'People can enjoy seeing it and hearing about its interesting past.'
The Bob Moog Foundation is quick becoming a repository for a variety of donated artifacts from music and synthesizer enthusiasts from all over the world. The foundation is stewarding the preservation of donated items including: synthesizers, controllers, photos, schematics, correspondence, equipment, literature and more. Interested donors can contact the foundation at info@moogfoundation.org."
Update 11/15 via Mark Pulver: "Interesting! So, back in February of 2002 I tripped over an eBay auction that featured that controller. From history, I knew that it had been stolen from a gig in Cleveland many moons prior (1974?). I got an contact email for Roger, wrote him, and heard back. He was pretty stoked. We flipped some email and Roger has said it might be hard to prove ownership. I got Bob Moog and Roger Luther involved as well, and RogerL came up with that picture of him and Bob (and the controller).
He contacted the police, but the case had long been closed, so he contacted the eBay seller ("I found it in a storage unit..."). After some nudging and more proof digging from my side and some back and forth, he convinced the seller to let it go - but only after paying the asking price plus shipping to get it back. :("