Hiya, cat.
There are a ton of 14mm atties that would work just fine with your OG cup. REOSMods has the nofear as an example. Others would include:
* speed
* viper
* cyclone
* graal
* nutz
The list is longer than that - these are just a few to give you some ideas.
@Vapefiend has a very nice collection of MTL 14mm atties - perhaps he can pop in here to expound further.
As for acquiring one, there is the nofear as I mentioned. Used, the classies here often have treasures like these available and there are several bottom feeder groups on FB (just search "squonkers" or "bottom feeder atomizer") that have buy/sell areas. New,
fasttech has an arsenal at the lowest prices (just search by the model names).
FWIW, I really like the viper V2 and graal.
Happy hunting.