2007 Berligo Replacement Key?

[Dogbash]

Hi everyone, I have a 2007 berlingo 1.6hdi and I only have 1 key for it. The 1 key that I have has a dodgy lock button, its basically broken off inside the case.

Rather than going to the dealer and getting ripped off, does anyone know any other way I can get a replacement key for it?

Thanks