Yep, Farnells have the same, with the advantage that they're a stone's throw from my office in Leeds, but at @£4.50 a knock,:which is fine, as long as I'm sure that it'll fit once I've taken the hacksaw to it.

I've emailed Yamaha's HQ this afternoon to pose the question: What's the point of putting this socket on all your gear if your customers are precluded from using it?