For those who were requesting a site/blog badge to publicise the Great Repeal Bill Facebook group, I did consider composing one ...
... but quickly discarded that idea, and asked for help from a true professional instead.
Please feel free to use it widely, and link it to the group HERE (see sidebar for an example).
UPDATE: Someone e-mailed as they were unsure how to apply this to their blog. First save the badge. In Blogger, go to the 'Layout' tab and choose 'Add a gadget', then select 'Picture' and browse for the badge on your computer, adding the Facebook address in the URL box. Simples.