gatrapper;
I have been on 5 elk hunts killed a bull each time largest was a 340" 6x6 smallest my first was a 250 5x5.
Your 270 is plenty powerful (especially if you use a bonded bullet like a NAB) enough for any elk at reasonable ranges key being reasonable range.
If you are set on up gunning then I can not recommend strongly enough you begin at 30/06 or 7mm Remington Magnum. The 7mm RM is the worlds most popular belted magnum for a reason excellent performance and the most mild recoil for any belted magnum. Most rifles come today with the option of a factory MB or a threaded muzzle so breaking the rifle should be no problem.
The 30/06 is still as popular as sliced bread for a reason its very accurate and more than powerful enough for anything save for the big AK Grizzly and Brown bears
But as has been stated I do some serious looking for ammo availability to choose your caliber but I will say my local Cabela's had most popular rifle caliber hunting ammo in stock the last 7-8 times I was in there, all be it rather costly.
AS you do not reload and finding reloading components is actually harder than finding factory ammo you will almost have to choose as popular a caliber as you can to help insure you will be able to buy ammo for it. So calibers like 30/06, 7mm RM 300wm or 300wsm will be solid choices.
As far as what rifle I envy your budget of $2k as I could never afford such a rifle. AAMOF my most expensive rifle and optic combo doesn't cost $2k more like $1600.
I can whole heartedly recommend the Tikka T3 as I own two and both are 100 yard 1-holers with my reloads.
My friends own two Tikka's in 300wm also great accurate guns.
Here's two good sites to check caliber specific ammo availability:
In-stock best prices for 300 WSM Ammo rifle 180 grains | Best 300 WSM Ammunition rifle 180 grains - AmmoSeek.com
ammoseek.com
Browse in stock rifle ammunition from the top manufacturers such as Remington, Tula, Wolf, HSM, Federal, Freedom Munitions and more. Find and buy bulk rifle ammunition ready to ship.
www.ammobuy.com