Well technically all you need is a Firewire cable. DVCPROHD over Firewire has been supported in FCP for nearly two years now using SATA, ATA, FW400 and FW800 drives(though 400’s are a bit dodgy for this esp capture). If you wanted to view back on an HD monitor you’d go back through the camera. It’s only if you wanted to view on an SD monitor where you’d need to get some extra hardware for the HD-SD downconvert but I’d recommend instead getting an HD monitor. They are pretty affordable these days compared to before.
Noah