Austin - My current preference is a 6.5 X 284. Lothar Walther match program barrel, custom ordered built to my specs Nesika action, custom McMillan stock built to my spec, 12-42 Nightforce on top. Now add in the price of accessories, the reamer, brass and customized dies and there is well over $4,000 in this rifle before it ever made it to the range. The barrel has 1500 rounds or so through it and it's looking a little rough although it still shoots pretty well. Replacement barrels and smithing aren't inexpensive either.
The least expensive way for you to get started would be something like a Savage with an eftermarket barrel in 1-8.5 twist chambered in .260 with a decent 20 minute rail, decent rings and a decent variable power scope with a minimum of 20 power. Get Redding dies BUT there is no need for anything fancier than a standard full length sizing die just starting off although the benchrest seater die is pretty handy.
Get a big box of 142 Sierras or 139 Scenars, some H4350 and H4831 powder and work yourself up a load, At short range using a chrono will help eliminate those loads that just won't work due to not enough velocity or too much extreme velocity spread,ES). Don't waste time and barrel life agonizing ever every last bit of developement, what you want is a load that has enough velocity, a small enough ES, and enough accuracy. Then start shooting at long range.
Then you need to shoot. Learn wind reading skills and learn how to analyze your targets, what horizintal stringing means, what vertical stringing means. You may want to start off at 600 just because it's easier to get started and get them all in at least the 9 ring before moving further out.
I've been outshot by plenty of guys with less fancy and less expensive rigs than mine the first couple of matches, at least until I learned how to drive this particular rifle. And that's really the bottom line, getting enough practice in until you can regularily shoot to the limits of what your rifle is capable of, then you can start thinking about a seriously expensive custom.
Unless you've got some serious dicretionary money, then just go whole hog right off the bat.