Source for Security Cable for TP750Cs

[ucklw08 <ucklw08@ucl.ac.uk>]

I have the TP750Cs which has just a little metal loop which can be
extended past the edge of the thinkpad by moving a level on the base
of the unit.  The level also locks the keyboard closed.  Since all
of the newer units have gone to the MacIntosh (Kingston?) locking
device, where can one get a security cable for the older TP750's?