I have the vaporizer in the title. It was gifted to me and came with the mouthpiece/base and several coils for dabs. I need replacement coils and I haven't had any luck on finding appropriate ones. I'd consider buying a whole new mouthpiece/base set up if its of high quality and makes replacing the coils easier but would prefer to just find the coils.
What company makes the mouthpiece and coil it came with? Look up the company's site or go to your LHS and buy a new mouth piece and extra coils. I use the 710pen piece and coil. I use the 30w Eleaf as my ecig and dabs and they carry the coils at my local shop. Maybe your friend knows?//static.grscty.com//public/style_emoticons/default/confused_2.gif
You can find these all over dhgate.com for cheap, those coils/atomizers come in all sorts of configurations where they use cotton rope or ceramic bars, these work best! If your looking to replace the whole head and atomizer at once search Google for "Budderball X5" and you should see listings on Dhgate with some sellers or search on Dhgate for the words "Globe atomizer" Only downside to Dhgate is shipping takes sometimes 14-21 days give or take a few but the shipping is free and things are dirt cheap.
You can find replacement coils at your local headshop, ask to see coils for a vapor globe. The coils for the vapor globes are usually low quality and come with silica wicks that burn and are unhealthy, and most of the time are way overpriced. If you are looking for a replacement atomizer to use with the istick i would lean towards the source orb 3 or the atmos kiln.