Betamax tension measurement tape

I want to measure back-tension and forward-tension of my Betamax
recorder. More info here: http://www.palsite.com/tools_tape.html. Does
anyone know where I could buy one of these? Thanks

 

I have a Betamax tension cartridge which I want to hang onto, but
don't overlook using a fish gauge on a dismantled tape. This can give
pretty good results though you have too fool the microswitches and for
some tests the rotation sensor into thinking a tape is present and
spooling. Actually, holding the microswitch and spinning the unloaded
reel by hand will do this while feeding or pulling the tape and fish
gauge to/from the reel under test.

. Steve .