Prime Lock Mystery Cache

The cache is at the posted coordinates, but you must sign the log to count the find! Please search only during daylight hours, by request of the business owners.

Congrats to tasmo and LJFL for the very quick FTF!

The cache is not large enough for trade items. BYOP.

Here is your task...
You're looking for a prime number under 1000. That certainly narrows down the possibilities, but here are a few more clues for you.

Ignore one digit and you're celebrating silver.
Ignore a different digit and you're legal.
Ignore the other digit and you're in Nevada, but the government won't talk about it.
None of these clues results in a prime number.
One permutation of all three numbers results in another prime, but only one will open the lock.

Sure you could settle in for a long boring session of trying random numbers, and I'll never know. But I hope you use your noggin and figure out the much smaller set of possibilities for this cache!

Thanks to Dr. Tom and his staff for permission to place this cache. Please use reasonable stealth and be aware of the presence of animals!