John Ostler makes his own Reg, but i dont know if he sends them through the post for fitting. To have the job done properly you need to Send the gun to John.
My guns are standard Ev Regs that have been set up by John with some alterations, the results of which are superbly consistant set ups.
100% recomend Ostler for a world Beating set up
you will have to keep ringing at the moment thoguh as John is a bit slow off the mark following a cycle crash a few weeks ago, if all else fails leave a number on the answer machine asking to be rung back. Worked for me yesterday