Senior fares are about 30% less than this, if you are 65+. Availability does not match unrestricted fares, and they are not bookable online.
If you book online, you will be 1/4 of the way to a free ticket. Then get the Southwest Visa card and you will be halfway, with 11 months to pick up the other 8 credits from MCI, La Quinta, Hampton, or whatever.