Looks like this is a nationwide clearance offer. There's a large range of these in the Westwood BHS located near the tills. These usually go for £10+ online i think.
Also a decent range of alcohol gift sets available for £3-7.50, those are near the door.
They're roughly 20cm/8 inches tall, and have the removable microwaveable lavender scented wheat bags in them.
I preferred getting these ones with the removable wheat bag, rather than the other versions available from other shops that make you put the entire thing in the microwave.
These removable ones seem much more hygienic to me.
Image is randomly taken from google.