Hand Held Racers Density-Altitude Calculators

[ARDUNDOUG@aol.com]

Group,
    Does anybody know the source of those little hand-held calculators some 
of us use to help in pill changes or figuring density altitude at the 
drags/lakes?
    Monte Osborn, the guy with the Ardun powered 37 2-door that went 142 at 
Muroc 99, wants to get one. Mine is one of the Jeb's models from a few years 
ago and he's supposed out of business. Any help would be 
appreciated.........Doug King