might want to try one of the tikka forums or over at snipershide there is a tikka thread sticky under bolt rifles that mentions a few smiths that do tikka work. I know these guys to tikka work: http://shortactioncustoms.com/
also pete lincoln with roedale precision does the tikka barrel nut available in prefits.. just his shop is in Germany. he used to have tikka action wrench and nuts available on his site for sale, just haven't looked in a while.
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