Remington makes the 700 in .338 RUM (Remington Ultra Mag). But if you're looking for a long range target platform, I'd suggest picking up a Remington Sendero in either 300 RUM, 7mm Mag, or 7mm RUM. They will all be powder hogs, but they are a superb platform to build from, and are pretty top-notch right out of the box. My Sendero 7Mag was capable of 1500 Meters reliably so long as I held my end of the bargain.
"Why is is called Common Sense when it seems so few actually possess it?"
Guns only have two enemies: Rust and Politicians.