I have googled and googled until I am sick of googling, but all I can
seem
to find is a 5w one (30w equivalent) which is way off the mark!

This one ?
http://www.lampman.co.uk/javastuf/ht...ERG_1_Qwt.html

I'd agree - 5W is going to be very feeble.

Yup, that be one of them!

I need them to have at least 650 Lumens of light output, and have an
ES/E27
cap

Is there such a thing out there!?

I've not seen any. You might get halogen equivalents. Or you could save
some money on bulbs if not electricity and go for Screwfix's long-life
variety (I have a stock and they do last significantly longer).

If all else fails, I may go for some of them - I always seem to be replacing
the damn things!

Thanks for the suggestion!

Sparks...