Vaporshark rDNA40 mod was selling for $189, but they have a "new" mod coming out so they lowered the price to $130 to clear them out.
For the 4th of July holiday, VaporShark.com is having a 15% off sale. The mod is well-respected, small and high quality and a good high-end battery is included.
rDNA The Next Generation
The coupon code is "sharkweek"
That should get you down to about $110, with a battery and it has a USB charger.