NoxoN probably doesn't sell these antennas separately. You can contact the importer in Zofingen for more information. In theory, any (active) antenna with an MCX connector should be usable.
According to my research, the following applies;
Devices that were produced or imported into the EU before 28 December 2024 with a different connection, such as micro USB, may continue to be sold. However, these regulations do not automatically apply in Switzerland, which is not a member of the EU.