Just to finish off / update this thread, I've successfully swapped the acrylic case out for the Van Daal metal case.
The only slight issue was I needed slightly different length stand-offs to those provided to attach the board to the top of the case and to stop the Plexi CNC glass from moving around too much. I wasn't the original builder of the board so could just be that the OLED needed some longer stand-offs when it was assembled (as mentioned earlier in the thread). No big deal.
Didn't go with the Eagle knobs from Mouser in the end, went with some black 1900h Davies clones from Thonk
https://www.thonk.co.uk/shop/1900h/