If you want the currently available extra cards, you're most likely better off going to Amazon to find them. They have all of the Gambit cards + both sets of Solo/Co-ops. The Geekstore is currently half of that, though it does contain the Pirates solo/co-op which wasn't pictured on the StarRealms.com blog.
Just noticed that myself. Wish that I had known before I bought it at the Geek Store. I'll either buy the set at Amazon as well or figure something else out.