Available as an assembled Module and as a DIY project.
This Module is currently available.
Specs are approved by the manufacturerSSI2131 based VCO
This is a solid VCO using the SSI2131 chip. It is very stable and will track nicely over 10 octaves. It has the stock outputs; saw, triangle and pulse, along with a pan-pulse waveform.
These merchants probably sell this module. Huh?
Nonlinearcircuits Moldy Rapture VCO