It really depends on the grounds. If the trial/test is at a refuge open to anyone, no way. If the grounds are privately owned, I would be inclined to take a pup. Now I probably wouldn't take an 8 week old. That is an awful lot of sight and sound stimuli for one that young, but a tad older, yes.
And what Gavin said. Pup is on a short leash at all times. Not all humans love puppies and it's completely disrespectful to let a pup get in the face of a working dog.