I definitely checked my local Sainsbury's and never saw any pie pans, only the scalloped edge pans. I will take a look at Wilco's tonight, that link said they were out of stock online, but hopefully my local store will have some.
If not, do you think I could use those flan dishes to bake my pies? They aren't very deep, but I don't know what options I would have if I can't find any pie pans, unless I try to make some tarts or something instead....