Transporter rear offside glass replacement?

[aknapper]

First post but many views. I've managed to crack the rear offside glass and am looking for ideas to find a suitable replacement and seal. It's an E-reg Komet transporter. I've tried the VW heritage replacement glass but it's about 15-20 mil too long (! grr) And the seal is for the driver side. So off they both go back to VwH this week.
Does anyone have any ideas of how / where to get a replacement glass and seal? I live in Glasgow.
I'd really not prefer to have to grind out the window frame the extra 15-20mm so as to fit the VwH glass.
I've asked Peter at Wagonbuild in Inverary if he's got the right dimensions in any of his avail glass - waiting for a reply.
Custom window replacement people seem to want to grind first...but I will take it in for them to look at. If they insist on a grind, I'll just do it myself.

Does anyone have any ideas? And, in case I am completely stupid, are there different seals for the rear windows since they are trapezoids and not rectangles??

thanks
A

[Plasticman]

Post up a picky of the hole you have , factory or van conversion

mm

[aknapper]

No pic avail until Friday - sorry

[aknapper]

So we ended up at FGA Windows in Clydeside for a look at the window. Turns out it is laminated glass and likely installed during the conversion. relatively simple to sort out - cut a new template and pop in with old seal.