Next cheapest I can find is £22.99 Play.com and £29.99 HMV. This is the season 1 and 2 boxset.
"The year is 2151 and Britain has launched an armada of spacecraft to protect her interests in the cosmos. Amongst the ships is HMS Camden Lock, whose crew has been charged with the task of bringing peace to the galaxy, while persuading encountered life forms to relocate their businesses to Peterborough. Led by the overtly optimistic Commander Henderson, a hero to none but himself, and his First Officer, York, a visionary scientist with a penchant for sadism, the rest of this motley crew consists of a staff so eclectic, youll be glad theyre not roaming the Earth. A first rate cast and sharp writing combine to create a comedy of inter-galactic proportions."
Hope it helps some people :D