Antelope huntin' Wyoming style!! Doesn't get better! Congrats.
1st off . . . 7mm zeroed in to 200 yards? Just put the crosshairs on the kill zone and you'll be good inside of 200, and easily out to 300. Watch the cross wind. Don't move much, just an inch or so on the animal.
"quality land with lots of animals on it in" . . . Lopes will be every where. It's not like white tail, goats outnumber people in WY. You'll see goats everywhere you go. Have you been to the G&F sight and investigated "Walk-in" areas? Go to
http://gf.state.wy.us/wildlife/access/plpw/huntingwalk/niobrara/niobrarakey.asp
Wyoming has a program state wide where the G&F in cooperation with land owners allow hunting on private lands. One of these programs is called Walk-in areas. Nibrara Couty doesn't have a lot, but there are some. Map #1, area 3 is in your area. And area 5 in Map #2 has walk-in also. This one is near the afforementioned Morrisey Rd.
As you look at these "maps" of Walk-ins, notice some of the map is blue or yellow?
Blue is public land owned by the state. You can hunt this. Yellow is owned by BLM. You can hunt these too. You'll be smart to get some BLM maps of you area. They show public/private lands, roads, etc. Maybe get a Wyoming topo atlas by DeLorme. Local book store should have them, or order you one.
One thing to remember about public lands, you can only legally hunt them if they are accessable via a "publicly maintained road". If you see a sign that says "Private Road", or Has a gate accross it, you cannot get to it. There is a
LOT of public land in WY that is landlocked by private.
Don't be afraid to knock on some doors! A lot of property owners are glad to have Antelope shot on their lands for free. They eat crops and are very hard on fences.
As far as a list of property owners, you might try and contact the chamber of commerse in say Lusk, or even Riverview (if they have one). Small towns often provide lists of property owners.
If I've missed somehting, let me know. Always glad to help.
One last and important thing! Get the hide off you goat, wash it down, and get it on ice as soon after knock down as possible. Doesn't spoil, but gets gamey quicker than most critters. Take care of the meat and you'll have some delicious table fare when you get home.