Place to buy a Superdrive in the UK?


Does anyone know of a shop in the UK that stocks a Superdrive for my Powerbook 12"? It's just gone out of warranty, so that means that I can now play around with loads more upgrades and I thought it would be nice to finally have a DVD burner.

If there aren't any in the UK, does anyone know a good and reliable store that will ship to the UK?
Apple says this about up grading the mac minies,
Depending on your wireless needs, Mac mini may be upgraded with an Internal Bluetooth, an AirPort Extreme Card, or both. Internal Bluetooth Modules and AirPort Extreme Cards are not user installable on Mac mini, but if these options are desired at a later date (after purchase), Mac mini may be taken to an Apple Authorized Service Provider for installation (fees may vary, depending on provider).
So hopefully the superdrive an the powerbook will fall into the same category? I'm sure if your willing to pay they will do the work.
I'm willing to do the upgrade myself :). It's more fun that way, and I have already upgraded the hard drive before on my Powerbook 12" and my iBook 14". So I'm well prepared for stripping apart my Powerbook.