Fuel filler pipe help needed!

Hello all basically my fuel tank had a hole in it so took it off and sent it away to be fixed but I managed to loose the pipe that goes from the filler cap to the fuel tank. I took the one off my brothers project for now but it didn't fit, it was to small and wouldn't fit over the filler pipe. mines a B reg and my brother said it's because originally it would have been a petrol engine (now a 200tdi) is this true? If so where can I find one?? All the ones on eBay are the same diameter all the way up where as mine was wider at the top end.

Not sure which one is yours





Hopefully you can tell from the pics...

Looks like it's 8 on the second picture. Looks thicker at the top as well

You could always order it from a place like Craddocks and give them your chassis number when you buy it, that's what I've done in the past