You'll have to go to second-hand markets.
If you have a system that you need to support that is using an older version the process is (1) buy the current version (2) pay a small fee for a "down-grade version" licence
Going from FM9 to FM12 requires the same amount of effort as going from FM9 to FM15. FM 12 has the same advanced graphic engine and file format as FM 15. If you want to make it easy you might want to stick with FM 10 or FM11.