disk II repair

["Dakin Williams" <ddwilliams@bosco.meis.uab.edu>]

    This past Saturday, one of my Disk II drives seems to have finally 
broken.  Specifically, the switch which detects the write-protect notch
seems to have failed:  all disks are reported to be write-protected, which
prevents writing to the disk.

    I took the cover off the drive and looked at the switch, but nothing is
visibly wrong (ie no loose wires).  The button on the switch still moves up
and down when pressed, and makes the expected 'click.'

    Has anyone experienced a failure like this before?  Does anyone know
where to get a replacement switch?  Or, can anyone recommend a shop that
fixes Apple II drives?  I have a feeling that it might be cheaper to buy
another used drive on ebay, but I'd like to look into fixing this one, for
loyalty's sake.

Dakin