Purchasing and picking up train tickets for Naritaa - Kyoto - eviltoast

I’m arriving at Naritaa Airport at 08:35 and would like to continue my journey by train to Kyoto.

I’ve found I can take the Naritaa Express to Shinagawa. From there I can take the Shinkansen Hikari on the Tokaido line to Kyoto.

The problem is I’d like to reserve/purchase tickets beforehand. I understand I can purchase them online and I’ll need to pick them up. It seems that I can’t pick them up on Naritaa airport or in Tokyo because the Tokaido line is operated by JR West whilst Tokyo is in JR East.

If I purchase a train ticket online from Naritaa Airport to Kyoto where can I pick this up on the Naritaa airport?