If you have $1200 plus an action to work with, you've got it made. Less than $600 will get the action sent to Douglas Barrels for the caliber/contour/groove/twist barrel you desire, installed and chambered for your ideal cartridge. Another $600 gets a Mc'Edge stock.
If you're not sentimentally attached to the A3 stock, and it is in good condition, you can sell it for $300 to $350. If the heavy .308 barrel is from a custom maker and in good condition, you should be able to sell it for another $200 to $250. At that point you're only out of pocket for $600 to $700. Money left over for a good piece of glass and/or after market trigger and/or plenty of ammo/components to sight in and practice.
YMMV...
