Moving a gas meter outside and laying new gas pipe - help needed

[nmh]

We're doing a major renovation and need to change the location of our gas meter to outside and lay new gas pipe under the drive (it's currently very shallow and old).

SGN are responsible for meters in SE22 but their lead times are 12 weeks. Can a third party do the work? Can anyone recommend someone?

Btw - we're with Octopus Engery and energy suppliers can only move the meter itself 1 meter and on the existing wall. They cannot touch pipes etc. 

Any help - advise MUCH appreciated.

Thx