Italian Motors is the X125 (Maxter) importer and, right now, the only seller as it is brand spanking new on the North American market. So the link I gave you is how you buy it. You can call them with questions–they’re pretty easy to talk to.
BTW, note that the price does not include an engine mount. Not sure if the mounts for other TaG motors work, as I bought a new kart at the same time and the mount came as part of the overall package.
Don’t think TM makes a TaG package that is imported to North America.