Something like this will give you 50 volts AC. At three amps.

https://robu.in/product/high-quality-24v-0v-24v-3a-center-tapped-stepdown-transformer/

For the most recent discussion, using a triac controller, the requirement would be a 1:1 isolation transformer.

 

Something like this will give you 50 volts AC. At three amps.

https://robu.in/product/high-quality-24v-0v-24v-3a-center-tapped-stepdown-transformer/

It is a 24V step down transformer, how can it give 50V. Am I missing something?

 

It is center tapped, each tab side is 24 volts.

 

I am not aware of the vendors in India, so I have no way of knowing where to get an isolation transformer. That was the best I could come up using the vendor given. I was a bit surprised that it was in English.