Had a look in my local Maplin a few hours ago and found a number of Domia Lite products - basically the same products as Bye Bye Standby - at some good prices. Appears to be instore only.
A few prices off the top of my head:
Wall switch £7.99 - £9.34 for the BBS equivalent at Amazon
Lamp dimmer socket £8.99 - £10.74 for the BBS equivalent at Amazon
Key Fob £4.99 - £7.94 for the BBS equivalent at Amazon.
They had most, if not all of the other accesories. Unfortunately I didn't have time to make a mental note of all the prices. Not huge savings I know, but it adds up if you buy a few items. They were selling the BBS starter kit instore, which is not online, but unfortunately close to the silly RRP at £27.99.