It depends on where you work. If in the emergency room where it gets hectic, 35 might not make it. Scribing is not necessarily about typing speed, but how fast you can complete the EMR chart with all the necessary information (which obviously, faster typing speeds help to speed up completion). You also need to be able to type fast enough to write down everything the patient and physicians say. Also beware that some hospitals require laptops, which means you will be standing and writing with only one hand (the other hand is holding the laptop).
If it is in a primary care office or something like that, perhaps typing speed would not be a problem.
There are many online resources you can go to practice speed. In fact, there is this fun game that I play that helps.
http://zty.pe/