2007 F430 a/c compressor clutch replacement?

a/c isnt working and took to a shop and had the freon charged up was 8 oz low..

but the compressor never turns on- i tried to manually test the clutch with a separate battery into the wiring connector on the compressor itself + and - and the clutch doesnt lock up--

is there an aftermarket supplier for the a/c clutch-- ive emailed ricambi- havent heard back yet