Multi function steering - part numbers for buttons?

Hi

I retrofitted a four spoke multi function steering wheel on my 2007 Octy II, and it has got buttons for radio and phone. But I'd really like them to switch places. On my steering wheel I have radio buttons on the right and phone buttons on the left. As I have a "lefty" car, and as I almost constantly drive with my left hand on the wheel and the right hand on the gear shift, I don't get the most out of the radio buttons. Actually, I rarely use them, and thats a pity!

So my question is; are these buttons available in both configurations? I mean, can I buy left radio and right phone buttons and replace the ones I've got?

If so, do you have part numbers? My local dealer was not very keen to be bothered with such tasks as I had fitted this thing myself... :(