You can order these rifles straight from Tactical Operations. Rifles for mil/leo are top priority coming out of the TacOps shop, as they are actually working rifles. This, combined with the demand for TacOps rifles generates the long wait times. For prices, call TacOps and discuss with Mike. He will tell you how much what you want costs. They are not cheap, but Mike R. puts meticulous work into them.
Mike/TacOps uses the remington 700 as their standard action. There really is no need to go with a custom action with their builds, as they know the remington 700 inside and out and do a damn good job with it. The reason behind this is that the LE agencies are most familiar with the remington 700 action - easy for the armorers to work on. The rifles have an accuracy guarantee of 1/4 MOA with FGMM ammo. Again, this is because LE agencies use factory ammo, most commonly FGMM.
TacOps uses Crying Eagle Imports to import the rifles into Canada. They are based in the U.S., out of New Hampshire.