I'm not an expert on the Buchla stuff, but from my understanding the Electronic Music Box was Don's 200 system while it was being sold through CBS. This box we are talking about here was the portable performance version call the Music Easel, basically his version of the Mini Moog. I think its based on three different 200 modules.
Thanks, that's explains it. Good to see that Subotnick is still active. His "Touch," "Silver Apples of the Moon," "4 Butterflies" and "Until Spring" releases were favorites of mine in the 70s. I also remember seeing a metallic Buchla synth prototype at the Exploratorium when I went to see an Eno installation there in the early 90s.
In googling suitcase synthesizers on Google, I came across this interesting page of DIY analog synths from Brazil:www.recosynth.com
The "Phonedrone" synth, which uses a telephone dial from a rotary phone, looks especially fun:http://www.recosynth.com/?p=297