Just wondering if there is a way to get the smallest megalodon tube and the top fitting? I don't want the full kit, only the parts to be able to make the megalodon on the shortest setting. I see on the site that there is the bottom switch and 510 connector but I am unable to find spare parts for the top piece and the shortest tube? Would I be able to purchase the short tube and top piece? Only reason is because I'm going to run an 18350 and NOTHING else. Thanks for any help.