Long time lurker, first time poster.
Halfords currently have a 'Bundle Offer' for 25% off cycle shoes with purchase of pedals. With thanks to the OP for this offer:http://www.hotukdeals.com/deals/halfords-resin-bmx-bike-pedals-3-00-click-collect-1938144
Pedals for £3.
They have price matched Shimano R078 (don't know if this is a good deal) for £49.99. With the pedals and the discount, they are reduced to £40.49.
Don't know how long the bundle offer is on for.
Hope that helps someone