Under https://drive.google.com/file/d/1G4GAOEnymo2nV7JkjvM2DkCDP2_BoyzG/view?usp=sharing link, I have shared a small library - about a dozen [MB] - of selected soundscape pieces from ‘Doom 3’. Maybe you would wish to use it in your map, who knows. Not a big download, you could as well give it a listen. If I violate any major copyright, notify me, I will “C&D”.