I'm thinking that something like lettreset might
work - the line is only ab=
out 5cm
long (or 2" in old money).
=A0
I havent managed to find anyone selling 'lines' though, just letters.
At one time you could get rub-down lines, corners, etc (similar to
Letraset) for making PCBs, either to put directly on the coper-clad board
(they were resistnat ot the etchant) or for making the artwork to use
witha UV exposure unit.
I guess 'everybody' uses a CAD system these days, so such things are not
common. But they might still be avaialable somwwhere.
-tony