Unfortunately, unless you've got some friends in the UK who utilize Royal Mail, you're not going to get be getting London Calling you anytime soon.
NME and Aversion both report that Britain's Royal Mail will release a set of classic album cover stamps on January 7. The list is as follows:
Pink Floyd - The Division Bell
Blur - Parklife
the Clash - London Calling
Led Zeppelin IV
New Order - Power, Corruption & Lies
Primal Scream - Screamadelica
the Rolling Stones - Let It Bleed
Coldplay -