Hi Gavin, welcome to the forums
The most common way to achieve what you want to do would be to connect the YDP143 and the reface to a computer and then use a DAW such as Cubase, Reaper, Studio One, etc as the host. That's a bit clunky though and probably not what you want?
Until relatively recently that would have been the only option. However, there are now several USB to MIDI host devices on the market that should, in theory, make the whole thing a lot easier.
Check out the following:
CAMOLA USB MIDI Host Box. This is the cheapest but note that it only works with USB 1.1 connections. I am not sure what the YDP143 uses but knowing Yamaha it could well be 1.1, best to check though.
Next is the
Miditech USB MIDI Host, MIT-00155. I am not sure what version USB this uses so best to check with the manufacturer.
Finally, we have probably the best known and most expensive, the
Kenton Midi USB Host.
I hope that helps a little?