Assuming your perl binary was compiled with enough RANDBITS and that you can store the entire array in memory, than yes, you can pull out a random element of the array.

For example, the following code generates an array with 100 elements in it, and retrieves the value of one element randomly selected:

my @a = map { rand(10) }(1..100);
print $a[int(rand(100))];

__OUTPUT__
4.65349565896584
[download]

You should be able to do something similar, except that your array would be bigger. Basically, the amount of memory would determine whether Perl could handle the process.