There were 489 k-code Mustangs produced in 1967. 319 of them were k-code fastbacks. 205 fastbacks were produced with 4-spds.
If you give us more details about options, what's there, what's missing, overall condition, etc., we can probably tell you how good of a deal you got. In my humble opinion, if you bought a complete hipo engine for $2K, you did well.
Post some pictures if you can 'cuz we all like pictures!!