rear cat flange to back-box pipework needed

Hi All,
My backbox has gone, as has almost all of the pipework from the flange with the 2 bolts in it from the cat backwards.

I have got a motorcycle silencer from a Fireblade (same size as the Beat) which I'm going to replace it with.
Has anyone got a piece of pipework that could attach to the flange to allow me to attach said m/c silencer up to it, I'm not bothered about seeing a tailpipe out the back, so can mount it high up, crossways, as the original one does.

I know lots of people that have access to pipe-bending and welding have done this mod before, just cant get anything done here....will be in the UK in a couple of weeks, someone please help my poorly beat.
Hopes someone can help with this