BMW dealers used to sell it in a spray can years ago - not sure if they still do, and they might trade it under a different name - but its all black soft touch paint. NAPA often has interest to getg more unique products too.
Senotex is the grey textured coating that is found on the dash components of the Elise / Exige cars. I have not seen any color code, color name, part number, etc. It is only referred to generically in the manual as Senotex coating. It does show up in the parts lists as an identifier for these components.
Working on a restoration/cleanup. Need to re-work some dash components. They need to match.
Hope to find color specs and manuufacturer so i can locate.