Module is available as a DIY project only.
No info about availability.
Barton VCA Mixer (Grayscale panel)
This module is a combination of four simple VCA circuits run into a summing mixer. It was designed primarily to work with audio signals, being the final module in a system before going to an amplifier or recording interface. Each VCA his it’s own individual output which is wired to be taken out of the mix when used. This is nice, because you can “normal” inputs in, and just plug in the output when you want to do something else with it.
These merchants probably sell this module. Huh?