matt
to answer that question, the cad was designed to replace the holmes wright lantern, as it was old and was not being produced so parts were not available, as they are to be serviced ie, bulbs need replaced and colour filters need to be clean.. i believe the byne lantern is still available, to be honest all the test equipment is still available, but probably in storage at gatwick, you not going to destroy equipment which cost allot, even though it not being used. any other results that you get ie from city university for cad is still valid, after all they designed it for the CAA!!
the spectrolux is still available but in switzerland, you can google the test name and find the location and address for it..