If you have Acrobat you should be able to just select the map from the SG pdf and right-click save it separately as a jpeg. Preview for Mac requires you to copy it, and open a new document, which will be what you copied.
There is a sector map in Shadows of North America (p.77) as well, and that SG map is also in the Sixth World Almanac (p.178)—in color, even. Now, if you don't have those then it is a bit of a problem. I know Season 2 of Missions was all set in Denver, but I never played that. I will ask if there is something they made, though. Or PM Bull, since he's the Missions coordinator now.