For my 2000 Porsche Boxster, the A/C bearing was an NSK 35BD5222 bearing that measured 52mm OD 35mm ID and 22mm wide. Any sealed bearing with the correct dimensions should work. This bearing is readily available on ebay and other sites. Some auto parts stores also stock the bearing because it is commonly used in car A/C compressor pulleys.
|Original bearing removed from my Porsche 986|
|Side view of the AC clutch bearing|