Where can I find a Benz lps cartridge for sale?

One should not confuse Ernst Benz with Lukatschek. Lukatschek bought the company from Ernst and is the moving force by Benz since. But Lukatschek is not a young fellow
anymore and my have some helth problems. This may explain the shortage of the supply as my comrade Don put it.
Regarding the LP S (aka 'mr'). The cart is 16,5 gram so only suitable for the tonearms with extra weights or very heavy counter weight. Among my 14 tonearms only Triplanar
VII with its 4 weights and FR-64S with its 240 gr.counter weight can balance the LP S. Other tonearms will need extra counter weights for correct adjustment.

The other peculiarity one should be aware off are the
very strong magnets. The so called 'iron core' does not
allow strong magnets. That is why Lukatschek uses ruby
plates for the coils. One should be very careful with
(fastening) screws as well the nearness of other carts.
Because of the open bottom a screw can get 'fastened' to
the coils instead to the threads . My comrade Don broke
the coils of his ,uh, Ruby 3 by traing to get his screw
back while my (small) Hiyphonic MC-A3 was nearly killed
by 'embrace' of the 'big' LP S.