David Billington wrote:
I thought you were UK based. Might be best to email a photo to Rod
Donaldson at Source with some dimensions, he's on broadband. He may have
something stashed away. Not everything is on the site.

Blowing it should not be difficult, if it requires a flange at the top
then it will most likely have to have a punty mark at the bottom but
this can be ground out and polished. If no flange, just straight sided,
then the piece could be cut from the blown item leaving what you want
without requiring a punty.
The punty is the small piece of glass used to hold the glass to another
iron when the piece is transfered from the blowing iron.

Thanks for the information. I need to get a triangular spanner before I
can disassemble the lamp, then I'll take some photos and e-mail the
dimensions to Rod. If he hasn't got anything I might get back to you
about the glass blowing.

Best wishes,

Chris