The Mégane II Owners' Club

I have a bit of an issue: I don't have the locking wheel nut key for the alloy wheels on my Megane CC.
I have messaged the previous owner, but I'm not holding out much hope on that.. he pretty much gave me all he had related to the car.

Kwik Fit have quoted me £54 to get all four of them off, not bad, but that goes up to £80 including wheel nuts.

Does anyone know where I can get a tool to do this? I'd rather pay £50 for something I can use again than a one-off payment.

Panic over. The previous owner knew where the key was.
Nice one! I notice that the CC doesn't have the under-floor storage that the hatchback has.. (I now have both versions)

I'd still like to know if anyone has found a reasonably priced tool for this?

I have seen a set of keys for £100+, but that's a bit steep, surely?

My local village garage does it by welding a new nut to the top of the existing wheel bolt.
As they already have the welding kit, the cost is therefore only pennies each time for the additional sacrificial nut.

I would just change them out for standard wheel nuts.