Hi Stefan,
Your +/-50V requirement at the output really narrows down the choices for the driver. I would recommend that you take a look at the ADA4700-1 for that purpose. It has a very wide supply range, so if you use a +/-50V supply, it would allow you to go as high as +/-48V at the output. However, it is limited to an output current of 30mA. Adding a transistor at the output would help to increase the drive capability for your purposes, though.
I hope this helps!
Kris