If you have edit right in an SG you can use the /sg_music <filename> command to play the sound in your SG.
FactoryWhistle_01
FactoryWhistle_02
FactoryWhistle_03
FactoryWhistle_04
Since they are not loops, they will only play once when you enter your base. And since they are not loops, they also may not be the sound you are looking for, the ambient Skyway loop Ilocated didn't have the sound you described.