Welcome, you will find lots of info here. There are lots of .308 Win. shooters in this crowd.
The primary source is www.badgerordnance.com,
or from Marty's neighbour and buddy George Gardner at www.gaprecision.net.
You might get lucky and find a used one occasionally on the Emporium at Sniper County or in the similar section of Snipershide.
Badgers are also available from Brownells and/or Premier Reticle I believe. They are just plain dandy. The Warnes will work very nicely on Badger bases.
Good luck as you enter the world of LR with the mighty .308 Win. Buy some Varget and lots of 168 and 175 grain match bullets and give-it. Our standard load is from 44.5-46.0 grains depending on the bullet and rifle. We have best luck with Winchester standard rifle primers, Winchester (or BHA Match) brass - other guys might have other favorites. We load to an overall length of 2.830" since we want the ammo to feed through magazines, you can go longer if you single-feed.
If you need some drop tables I would be pleased to help you out, I believe some of that info is archived. One great fact about shooting the .308 Win. at long range is that the windage dope has long been figured out. Big challenge is applying it with skill and knowledge, and that takes a lot of shooting.