Had this aluminum plate laser cut a few months back and hand-wired it with Box Navies and a RPi Pico, and oiled oak for the sides. I missed my numpad, though, so I used my own laser cutter and made an external one from Masonite and textured spraypaint.
Left side numpad? That’s unusual
I’m not sure where it will live long term, but “southpaw” numpads are definitely a thing. They allow for mousing while doing data entry, and they mitigate one of the reasons some people do without numpads by allowing the shoulders to stay more neutral when the mouse is close to the right edge of the keyboard.
How much does it cost to have the plate cut?
I am in the US, so Xometry was pretty economical for my needs. I had three top and three bottom plates cut from 1.5mm 5052 aluminum for $67 total, tax and (free) shipping included. I added in a laser kerf on the swillkb plate generator that probably wasn’t needed, as the switches are in there VERY snug. If you were doing a plate for hand-wiring, that’s not a bad thing, actually. If you need one to mate with a PCB, I’d consider leaving it off, but it could have been the specific shop or really anything. There is a bit of luck involved in this process, which is basically a crude form of prototyping.