Hi,
I would like to travel from Shingu via Nagoya to Tokyo using Nanki limited express train and Hikari train using my JR pass.
I read a lot online about the Nanki train requiring some sort of additional ticket/reservartation/limited express surcharge, even if you own a JR pass.
But I wonder: where can I buy the needed limited express surcharge ticket? Is it possible online? Does the extra ticket include a seat reservation or not?
Please help with my confusion.
Thanks.

