Saurabh
This exists. In India. Our good old Indian Railways operates this train.

http://trainstuff.in/kashmir-by-rail

Udhampur to Banihal are bridged by road. Bridging train tracks by bus is an excellent idea. When we took the train from San Diego to Jasper, Amtrak shipped us from Seattle to Vancouver by road.

Friends in PRS or NR, how does one purchase this road bridge ticket?

It is still snowing heavily in Kashmir. Who wants to go?

This track between UHP and BAHL was supposed to be commissioned in 2017. Does anyone know what the progress there is?