Pharm,
You will need a donor action, or if you already have one set up like above mentioned in 30-06 or 25-06 you will needto have the old barrel removed and a new barrel installed. Lots of barrel options but I'd look at maybe a Bartlein stainless or carbon wrapped if you want to get fancy. Then send it to a smith to have it chambered and cut to length and crowned. Or plenty of pre-fits out there these days but not sure any chambered in .280.
If you go the rebarrel route I would give Shaen @ Shaen Rifles a call, he has worked on Tikka's and his work is fantastic. He also has some unique ideas on all things 7MM and they work:)
Plus he will have it back to you pretty fast.
