You could probably get them for less than $100 on vistaprint. No offense to anyone, I know invitations are important to some people, but I can't justify spending that much on paper. Especially when I know guests will eventually throw them away.
Mine will be $150 for 50, includes : invites, addressed rsvps, and individual guest addressing for outer envelopes. Really depends on your budget and style choice. Some options cost a lot more than others. But over $7 an invite/rsvp set seems a lot to me!
Go to Walmart/target or party city. Buy the cards you find appealing, and create a PDF of the invitation & how you want it to look. And then you can try going to an office depot or max where they have a Copy & Print Department. They can print them for you, I just printed off 50 for $6.