Radar Setup from c120 to e120w

I'm upgrading my boat from a c120 to an e120w display I have. I have a pathfinder radar and also a rd 218. I know I can't use an analog radar with the e120w. What digital radar should I use. Is there a work around for the rd218. it's in great shape. What type of radar cable do I need with a newer digital radar. I think I need a seatalk cable now to interface with my dsm 300. what cables, and seatalk components do I need to make that work?

Sorry for all of the questions but any help would be appreciated. Paul