First I will answer your question in that I dont have a used vape kit for sale.
However this guy does sell a smoke kit for a proton pack.
Since this is a Ghostbusters forum, I feel like I can safely make the assumption that you are making a smoke mod for a pack, trap, or something else. If that is the case you will generally need to activate it with a button other than the trigger on the actual vape. Is that what you want to do? Better help can be given if we know more about what you are trying to do.
I have been able to make an actual ape mod work in my pack. I use second hand Charon TS 218 and was able to solder a momentary switch to the momentary switch on the vape motherboard. This was after I destroyed a Smok Alien 220W trying to do the same thing. I also tried a stick mod and was not able to even open it enough to try soldering the momentary switch. So some clarification would be good.
My vent mod in use in case you were curious: