I pulled the sound effects from source files from Aliens vs. Predator Classic and Aliens vs Predator (2010) PC games. Just use extractors (FastFile Explorer
for Classic and quickBMS
for 2010) .
All the standards are there—weapons such as the pulse rifle and smartgun, equipment such as the motion tracker, atmospherics, Xenomorph sounds etc.
I wrote a soundboard/dice roller for PC. "Soundboard" on iOS also works reasonably well for playback on an iOS device.
We're at our safest when we're not working.