MGB limited slip source?

[SATURN.DPEARS01@gmeds.com]

     Hi folks,

     Don't take this the wrong way, I'm still running my ES Saturn (and
     intend to do so for the foreseeable future - may buy a '97 when the
     new body style comes out this summer), but I am looking for a source
     for a CHEAP? Quaiffe-type (mechanical) limited slip for a '71 MGB -
     tube axle. Can anyone help me out? If anyone has a used one they would
     like to get rid of, that would be good, too. I'd consider changing
     from a Tube to a Banjo type axle, too, if the price was right.

     '91 Saturn SC
     '71 MGB (in pieces for the last 3 years) "Monday driver"