Behringer ( perhaps with the help of Bob Keeble ) have done a proto of the ARP 1601 sixteen step sequencer, and are showing it on-line. They are wondering about interest in this as a product.
This would go with their 2600 replica, but this also could be used with any of their other semi-modulars. Behringer also has their 1027, 960, 182, and soon the BCR32 sequencers.
Here’s a short article in SynthAnatomy.