Where in London can I buy Stroh Rum from? Which central liqueur shops would be my best bet?

Here goes:

A really good friend of mine is a great fan of cocktails with Stroh rum 80%, but it is so, that it’s impossible to find this drink in Greece. The good thing is that I am visiting London in a few days, so I was thinking to bring back a bottle of this particular rum for him, as a surpise.

The thing is that I have no idea where I can find Stroh Rum in London! Additionally, if I actually find it, would it be easy to bring it back home? (meaning, would there be special “travel” wrapping upon request?)
Could you, dear Flutherites, perhaps, help me out on this one?

Unfortunately online shopping at this point is not an option for me(not before March anyway), and that is rather sad, ‘cause I have found quite a banch of online shops that sell Stroh rum and at a reasonable price (it’s not very expensive, it’s just not imported to Greece anymore).

Ps. I am to stay in Bloomsburry and since it is a central area (I’ve been to London a few more times before), I keep my fingers crossed that there will be a few suggestions…

Thank you:)