i don't know whether these are still available but when i was in college i
bought some registration pins (ithink they were a spare part) from agfa.
they were small copper pins with a small copper tag attached to them.
i found that they matched up with cheap chinese hole punches admirably. you
may have to try a few to get an exact fit.
to use the pins i just tape them straight onto the baseboard or to the easel.
julian watt