Well first off I hope you can find ammo at all. Second off, what is the twist rate of that rifle 12 or 10? The 12 twist you might max at 168gr bullets, which if done right could make it out to 1000 yrds ...but you may need some prayer to do it. You really need something thats 175gr and higher to be realistic about hitting 1000yrds. Sometimes you can shoot a 175 gr out of a 12 twist rate but thats hit and miss based on the rifle.
O and you really going to need something more powerful that a 10x scope. I would say at the very very least something closer 20x. More realistic to go for 25x +
Welcome to a money pit
O and as a fan of the .308, I would still agree with the others. The .300 win is better suited for shots 800+ yrds