Toyota have said they can supply a master key for £35 that will open the door but not start the engine. They thought it wouldn't set the alarm off but were not 100% on that. The engine start is push button plus a proximity fob which they can't supply. That's why they said all locks need replacing.
The auto locksmith was very helpful although he's not sure what he can do. He's looking into it for me.
With this further information is there anything else you can think off?