Good custom exhaust fabricator

[OccamsChainsaw]

Evening All
I have a 2002 M5 with a Milltek exhaust + high flow cats. It’s a lovely exhaust, but my god it’s loud! Unfortunately Milltek don’t make it any longer, so can’t provide a resonated version to quieten it down ... they’ve advised me to get a centre section with resonators custom made.
Can anyone recommend a suitable company to do this? There seem to be plenty around that say they can, but I’m concerned about putting black holes in that beautiful linear power delivery. I don’t mind losing a couple of bhp at the top, but affecting drivability is a no-no, so it’ll need to be an outfit that understands gas flow etc, and preferably has a dyno, rather than a “you want loud, yeah?” type.
Any ideas? I’m near Southampton, but will travel for a good job.
Thanks chaps!

[OccamsChainsaw]

Cheers fella. Why silencers instead of resonators? Don’t resonators give a cleaner gas flow, with less resistance?

[OccamsChainsaw]

Thanks gents, most helpful. I’ve just dropped Russ a line and will be looking at H&S tomorrow.