Determining production year

Hello, I am a new member and I have for only a few weeks been a
Enfield-owner. Bought a bike from Madaan Motors in Dehli, supposed to
be a 1965 Bullet 500, took 2 years to reach me...
Anyway, now it's here, and last week I visited the auto-registry to do
the paperwork, but with little success. They said the could not verify
the age of the bike from the very worn Indian vehicle document. So if
someone here can help me dechiffering the serial-number(s) into some
year/date, that would be fine. The bike has two sets of numbers, both
on engine and steering head. They are G2/54194 and E1/27194. From what
I have found here I suppose it is about correct with -65, but that it
probably is a 350 because of that?
Is it possible to get some kind of official statement from someone
related to the factory, like dealers or official clubs?

Regards

Leif Brynildsen
Lillehammer, Norway