Forget about modern rifle, too many hunters from an overpopulated Pugetopolis.
Archery or muzzleloading rifle willl bring a reduction of hunters. I like traditional muzzleloading rifles, the inlines are cheat rifles IMO as they are a modern rifle that complies with the letter of the law while defying it. My advise is to purchase a .54 caliber percussion "Hawken" rifle made by InvestArms, Pedersoli, or Thompson Center Arms Company. Pay your dues at the range to become proficient with muzzleloading firearms so that you get reliable ignition and have the requisite marksmanship ability necessary for the one shot challenge.
A patched ball with 80 grains volume of FFG blackpowder from a .54 caliber muzzle loading rifle will get the job done.