I know some people who have successfully used Ubiquiti's airFiber for point-to-point links. I think those run on the order of $5 grand for a complete installation (two radios, mounts, etc) of a faster-than-gigabit link.
We run some between offices across the street from each other. We were lucky as we didn't understand the minimum distance was probably more important than the maximum distance for this type of setup! They have run flawlessly at about 800Mbps for the last year.