I have these actual size scans, but no 210mm, however. I'm sure SK Grimes can make one if you mark where you want the lines using a loupe, ruler and measuring tape.
If you are talking about a bed scale, just put a strip of masking tape along side the first scale. Then set the camera on a tripod and, using a fine point pen, mark the distances on the tape next to the bed scale "pointer" as you focus at infinity, 50', 25' 10'. If it was good enough for Flashgun Casey at the Daily Chronicle, it should be good enough. No need to go fancy, the tape works fine and it's what most people used back in the day, anyway.