Rear box for E30 325 Touring?

[5678]

Suggestions on the best place to get a rear silencer for my 325 Touring? GSF don't list a touring specific one but the 325 box in there is £144.

[buggalugs]

I got one of ebay a little while back, was well under £100. Its not that great, heavy, bad quality welding, not that quiet. Still it passes the MOT.