Printed Clocks

I am wanting to print this clock on my Markforged Onyx printer; however the dial is too wide. If I can get two STLs of the dial split across a diameter that would make it possible to print both and join. I could do this myself if I had the SW part file, or could generate them if I had a dimensioned drawing. None of the online STL editors seem to support dividing a file in two or deleting half.