From the hand behind that spread of tickets.
The usual fare is about £88, but I got it for £69, so worth doing. I sometimes have to move around the train because split ticketing doesn't carry a reservation forwards, but often the seat I'm sitting in is not reserved, so I can just stay still. This doesn't apply on Scotland where the lowest price always comes up on searches for Scotrail tickets as the Scottish Govt did away with the need for split ticketing some years ago.
New member - I hang my head in shame at not noticing the valid registration request to join the forum for a direct answer. Sorry about that - it got missed in a fog of spam on 24th November and I have just been reminded.