This sound effect can be found on Orchestral Colours, which was made by Best Service.
https://soundeffects.fandom.com/wiki/File:46_F-sharp_SWLL-stereo.wav https://soundeffects.fandom.com/wiki/File:46_A_SWLL-stereo.wav https://soundeffects.fandom.com/wiki/File:46_C_SWLL-stereo.wav https://soundeffects.fandom.com/wiki/File:46_D-sharp_SWLL-stereo.wav