As riverrock83 and flyingpony, you can add an IMC to a UK national PPL, and you can still get that (in addition to an EASA licence), at a cost of £35.
The CAA haven't yet said definitively what happens if you don't have an IMC at the time you apply for an EASA licence, so there may still be the option to add it to an EASA licence up to 2014.