Sure.
They used 2 SXTs but with your setup you might be able to achieve the same using a L2 wireless mode like station-bridge.
http://forum.mikrotik.com/t/bonding-wireless/54769/1
You might also be interested in something like this.
http://wiki.mikrotik.com/wiki/OSPF_to_simulate_full_duplex_links_with_redundancy