Let's see where to start.....
Lone Peak Titanium receiver,
#4 profile barrel (personal preference is Lilja or Hart) 6 flutes in the barrel for weight savings
Holland makes a great brake. I would look into Vais muzzle brakes as well. just something to keep the muzzle from flipping up on you for faster back up shots.
run a Chet Brown "Pounder" Kevlar stock
Talley one piece base and rings
I would run a 5.5-22X50MM or 3-15X50MM Night Force, Leupold VX-5 HD, or S&B scope
I like Harris Bi-pods, but people have other ideas with walking sticks that are shooting sticks. your choice.
I would most likely armor's kote or cera kote the rifle
the recoil pad I would use is a Kick-eeze 500 series magnum. I personally like the 1-3/8"
now the challenge and the personal preference for caliber. I do not like 7MM, I do not like 6.5MM if you do then I would most likely go with a 7 R/M or a 264 Win Mag. both are tried and true performers. to tie into the barrel the 7MM would have to be a 1:8" or 1:7" twist barrel for the heavier slugs for the 6.5 I would most likely do the same. but with a 156 Grain limit I would not use the 6.5 MM for elk past 800 yards. which brings us to my calibers of choice 270, 300, and 338. since 338 is out of your specs then we can forget that one. the 300 I would suggest is either the 300 Win, or the 308 Norma. if you go 300 WSM it might not have enough speed to go to 1,400 yards. I love the Win Short Mags but the 300 is just something I am not real up to date on. as always use a 1:8" twist barrel so you can use the 200 to 240 grain slugs.
now the 270's: 270 WSM, 27 Nosler, 277 H-mag, or wildcat for your cartridge. I would use a fast twist barrel like a 1:8" or 1:7". Berger has some really excellent VLD heavy slugs for the 0.277" slugs.
lastly, don't build a rifle for you hunt of a lifetime, build a rifle to hunt with the rest of your life. I am working on a 338 Win Mag build as an all around versatile rifle that I will keep the rest of my life. I am using a Win 70 action, 1:8" twist for 300 grain slugs, #5 profile barrel with deep flutes for weight savings and rigidity, muzzle brake for fun, 5-25 Leupold VX-5HD scope with a #58 reticle, Jewell trigger or stock trigger, I have not nailed down the stock yet. but I have friends that might want to follow my pattern for this gun.
have a great time reading all the suggestions and I hope that your rifle is never dusty. I hope it is always by your side and I hope you walk with it your hands for many years to come.