Yep, it’s the Evolution stand.
The plates are heavy duty barstool swivel plates:
https://www.amazon.co.uk/dp/B076CD9...imm_5ND4V2R8Y2JA9CF9N073?_encoding=UTF8&psc=1
The uprights are 30mm square rolled steel from B&Q and fit snug in the saw stand. I bought a 2.5m length and chopped it in half:
https://www.diy.com/departments/var...be-l-2-5m-w-30mm-t-1-5mm/3232637200004_BQ.prd
M6 coach bolts, washers and nuts. 45mm length for attaching plates to uprights. 16mm length for attaching angle iron (also from B&Q) to plates.
The Canadian Arcade YouTube video shows you how to set it up if you need instructions.