re-ribbon a mic. where do I get the aluminium?

[misterlong]

Myself and a colleague bought 4 Apex 205s in a bulk buy. In doing the windscreen mod, we have discovered that one of them is sagging a lot!
Bit of a shame since the other 3 are absolutely fine.
I am gonna have a go at retensioning it, but in advance of the fact that I might break it, Does anyone know where i can get new material to make a new ribbon, or anyone in the UK who can do this job for us?
Any advice from people who have done it before?
Your help would be appreciated!!
long