Realistically, even a 'factory' gun might take some smith work. There are a lot of great ones out there. I'm an IBS guy, I don't shoot F-Class. Best bet would be to find a group of F-Class guys and talk shop. You can get priceless info and save a ton of money by sharing a cup of joe with the folks that have been there.
Good luck with your new rifle, there is nothing like challenging your skills against a standard.