With all these prefits hitting the market for Tikka, and with gunsmiths still hell bent on charging high dollar to thread on a barrel... its getting to be an easier decision to purchase the following:
1) Barrel Vise
2) Outside Action Wrench
3) Inside Action Wrench
4) Torque Wrench
5) Go/NoGo Gauges
With the above tools, you can thread on your own Tikka prefit without paying anyone else to do it.
The ideal scenario would be to find a group of Tikka shooters (like those on this thread) and share some of the above tools, as I dont imagine the average shooter is going to get much use out of go gauges, etc.
For a standard chamber, sure. Want something specific, a smith will still be necessary.