The price is the same as in Spain, the regulator seals come all installed, in an attached support (a screw) you get the Bella-Ville washers, it also comes with a bag with some lubricant, it also contains the O-ring that is installed in the body, that is, the kit is plug and play.Yesterday I contacted Utah Air guns and ordered a new OEM regulator with the newer brass piston. The cost was only $46.44. Don't know if the O ring in the body is included. If not, I'll just go with what's included with the regulator. I think all the regulator O rings will come installed. Looking at that witches hat photo, I think I could easily make one from the removable tip on a cheap mechanical lead pencil I have.