I found this on Eurometers ltd

"Created by Gill Electronic Research and Development in conjunction with British Gas plc, Eurometers manufactures the E6 domestic gas meter which is the worlds first solid state gas meter to enter volume production. The meter is approved by DTI/GOMB"

EUROMETERS LTD
Unit 11
The Quadrangle
Abbey Park
ROMSEY
United Kingdom
S051 9AQLocation MapTel:+44 (0) 1794 518411Fax:+44 (0) 1794 518422

They may be able to tell you who purchaced the meter if you contact them and explain the situation? never tried that before and its a hell of a long shot but maybe worth a go? the worst they can say is "we don't know" or "can't tell you"

based on the blurb i found it could be b/gas but who knows, if the meter was installed in 1999, thats right about the time of deregulation, (early 1998 for all domestic gas) and you've not had a bill in that time.. could be them...?

You could also pm me the full E6007... number and your mprn if you can find it. I can have a look on monday when i'm at work to see if i can find anything if you want, i understand you may not however, i won't be offended lol!