Where to Find Switch for Fan Speed Control?

Thanks for your answer. The last link shows a very like product. But I bet - ask them for a replacement cam rotation switch for their product, and they will send you .... in their minds, somewhere far away.

Sorry, that's what I can do with info provided.

Google Rotary Switches. You will just have to match it up.

When buying a rotary switch, be certain to know your true full load amperage draw. While most well made switches will easily handle the momentary burst load of startup, you will quickly overheat the contacts if the switches amp rating is insufficient. And having just built a paint booth with a 3 speed fan (single phase however) I noticed some of the multi-position rotary switches amp ratings were the combination of all the contact paths added together and not the load bearing rating for any one position. I am not sure why they would do this, other than trying to look better on paper. But attempt to use a switch with at least 20 to 50% higher rating than max continuous load. This will improve the performance and life of the circuit as well as not starve the motor of current when the contacts degrade over time from excessive heating and arcing when moving through the different positions. I hope this helps.

In case of hard to find the same switch(the original) think with looking for another and make modification

Modification no problem - the problem is to find ANY one with the same functioning.

I am thinking about going to relays.