www.uboatarchive.net has BdU's war diary and some KTB's of U-boats from different years. Some KTB's tell which type of torpedoes they shot during the patrol, others have torpedo shooting reports atttached where they state the torpedo types as well. BdU's war diary has some mentions about torpedo loadouts. Rudewarrior's JFO! mod has collected that info.
A mod like that would be very cool indeed. The info is sketchy though, and it seems the type VII's operating manual was not always followed.