My question is whether this is serviceable or whether the only way to
eliminate such a noise would be to replace the gas meter. It states on the
meter that it is the "Property of Transco".

That being the case, who would I contact about either route (if
applicable)?


I'm not sure, but I believe tampering with gas meters may bo some sort of
offence.

Perhaps try contacting Transco, seeing as it's their property and
responsibility.