The Archaeological Institute of America, San Diego Society sells plastic
centimeter scales used in photographs of artiifacts to indicate object
size. (OK, artefacts in Britain). Designed by the Museum Management
Program of the National Park Service, they are still only $6 for the set
of two:  19x3cm and 12x2cm.   Foreign orders are $7/set.  All postage
paid.
More information at  http://www.theglyph.com/scales.html   Sales help
our educational lecture programs that are free and open to the public.

Ron Fellows, CM
AIA, San Diego
http://www.AncientEmpires.org/mt