There are dozens of private train companies in the UK, although they work together as National Rail to coordinate fares & ticketing. To check train times & fares, use the National Rail website. This site shows train times & fares for all routes and all operators.
Below are price comparisons from the National Rail Travel Planner for Advance, Off-Peak, and Anytime tickets for the same day and time.
Advance ticket: £58.00
Off-Peak ticket: £79.00
Advance first class ticket: £164.50
Anytime ticket: £213.90