A lot depends on the twist rate of the Sako barrel. If it is factory, it is probably 1:10 which means with copper you are limited to 150gr max, more realistically 140gr.
@Virtus Precision UK only do 120gr, 150gr and 165gr in 7mm. 150gr needs 1:9 and 165gr needs 1:8 twist, according to the website. I have Schultz and Larsen 7x64 in 1:10 but I am going to try the 150gr though I think 140gr would be the sweet spot. Most 7mm rifles, 708, 7x64, 7mmRem mag etc are 1:10. The more modern 7prc is 1:8.
I think long term it is better to buy British where possible.