* diameter gives pounds force, have you figured out how many foot pounds you want. A starting guess is 100 pounds. Granger is my go to on machine tools/ builder parts and they have lots of US locations, ,, i can walk to the local one.
* air system/ air regulator to control rate of stroke.
* stroke basically corking tools push about 3 inches
* safety you need something to prevent pushing a piston through your fingers, the easy stuff is electrical but then how do you tie this to pneumatic? Possibly actually run with solenoids,,,
My playing has been with a reverse acting motor and keeping everything electrical
A guess is that most folks stop at the safeties, otherwise we would see a lot more.
has wanted a pneumatic corker, ask if he found someone to build one. There are a few pictures here on WMT