I have a 3D printable wall-mount for the mesh devices or any of Adafruit’s Feather boards. I designed it to use also with one of the Proto Featherwing boards that you get here -> Proto Featherwing
You can screw it on but I have found that hot-gluing it works fantastic! Then whatever Particle Mesh or Adafruit Feather board you are using can plug right on to it. There is a spot on the side to hot-glue a PCB antenna to it. You can download the STL file to 3D print one for yourself here -> Mesh Feather Wall-Mount
A small LiPo battery fits nicely between the Proto Board and the Argon as shown in the picture.