Do they sell prime grade of meat?

The meat in Mequite is very good. Unlike the nearby Walmart which puts preservatives into most of its fresh meat cuts. Read the label.

Yes, at the meat counter. Ask for Dee the butcher

Yes, they have a few steaks that are prime in their specialty meat case. They may be able to order other cuts.

I have to travel to st. George UT the meats they sell @ Smiths in Mesquite NV always seem to turn brownish quickly - that tells me their coloring.

It seems like I've seen pime grade meats there.

I have seen that they do. The butcher can provide you the cut you need.