$7000 is alot. I had a new 92% trane gas furnace and 13 seer AC unit installed for $3500.
I don't think the windows are going to do that much. Certainly not anywhere near the savings compared with going to a 14 seer unit over your old 9. I replaced my windows with Argon (non-tinted) and I can't say that I can notice a difference in how much the AC runs. Made a huge difference in heating in the winter, which was expected as the prior windows were circa 1930.
You'd have to save alot of energy to recoup $7000 though. I'm in OH so the furnace is more important here. Make sure you get several estimates as mine varied by as much $2,000 for even the same models. Of course with the energy costs out west, they may be just sticking it to you because everyone is updating equipment.