I got mine from Q stores at Brompton.... for my ill fated wedding.
If i'd known what was coming I would of turned them into a civilian jacket and trousers, dug a tunnel complete mit lighting and air, and made a break for Switzerland... not forgetting not to say "Thank you" to anyone who wished me a safe journey.
DONT DO IT MATE your life as you know it will come to an end!! all the shagging like bunnies will be out of the window!! you ever dare to upset her in any way even without realising it will end in torment for you, she will put on weight like a gluttonous hippo, she will wear velour tracksuits and high heels....your pad will be inundated with vulgar harpies in the disguise of other pads wives!!
If however you are best man then the QM's at Brompton will do em for you, however they are restricted for sizes during the wedding season