I did not use an application service to apply for the tag. The WSMR publishes yearly data on the draw results which permits you to optimize your chances of a tag. It took me some time draw the tag because I wanted the location (Rhodes Canyon) which has a reputation for big animals (36"+ horns, some 40"+), a winter season hunt (if I have to travel to the southern US, it might as well be to escape the Canadian winter) and an intact animal (for the last three years, there have been broken horn hunts, you can only harvest an animal with a broken horn). If you really want to maximize your chances of drawing an Oryx tag, you study the past results and select a less favourable location,(Small Missile Range, Stallion Range, etc), a time when the US hunters are after elk and select a broken horn hunt or perhaps something other than an any legal weapon hunt (There are specialized archery and black powder hunts. (Cost is the same).
To answer the question about rifles (handguns are not permitted on the WSMR), I am unsure. I have three that will do the job- bolt actions 270 Win and 338WM and a Remington 7600 pump in 35 Whelen. None of the promo pictures that I have received from the outfitters show any rifles with bipods- perhaps the weeds, sand, or insects prevent prone shooting. The pump is a personal favourite of mine and is good to 250 yards- the others a good at a greater distance but I probably would pass on a very long shot. Obviously I have to make up my mind soon to apply for an ATF import permit for the rifle. I am sort of tempted to just purchase a new rifle and scope in El Paso Texas, if I fly down for the hunt. Any advice from members on rifle selection? Also I am unsure if I can take my handloads down on the plane. Perhaps another reason the sight in the rifle with factory ammo or just go whole hog and purchase new equipment. Thanks for any advice.