A BLF A6/Astrolux S1 with a 18350 tube is super pocket friendly. There may be a 18350 tube that would fit your VG15S. I am not sure which tube would fit but I imagine someone on here does. I use to carry a DQG Tiny 18650 all the time but, it is a side switch TIR light so that might not be to your liking. Super small 18650 light though. Think I saw a sale on the Nitecore MH20 if I remember correctly. Nice little pocket thrower with still a bit of spill. Lumintop SDMini is similar in size and output of the Nitecore as well if you can find one at a decent price. Manker makes a 14500 pocket thrower, the T01. All of those are side switch lights though.