These are quite a rarity i'm afraid - You're best bet might be to have a conversation with a site & see if you could work with them to pull something together.
I took this approach with Apocalypse Airsoft (Detling, Kent) & we had an evening to night game in June, we got a total of 65+ along to the event & it was enjoyed by all & bought a new dimension to the normal skirmishes etc.
Would I organise another event - Potentially, it was friggin hard work but very rewarding, maybe after Xmas though as work wise i'm just flat out & would struggle to find time to organise another.
UCAP Sandpit / Pit (Bluewater) organised a Zombie / Halloween / Night skirmish last year which was pistols & shotguns only - Never went but saw feedback & everyone spoke very highly of the event.
We've plenty of sites in Kent - Latest is BushValley Airsoft in Lenham near Ashford, chaps who run it are eager to cater & please so they'd be a good site to aslo have a chat with.
Lastly - A CQB site has recently opened called 'After Dark CQB' which I think runs on a Wednesday evening - I believe there's a Facebook page & it's run by a guy who goes by the name of Jon DarkwaterAirsoft, take a look.
Hope the above all helps
Mike
