G'day just passing through to ask a quick question

G'day i don't surf, but my American friend does and he is here in Australia over his Birthday and i wanted to get him a unique gift. I was thinking of getting him a silver proof coin commemorating surfing here in Oz but i'm not sure if that's a horrible idea. I was wondering if any of you would mind giving me ideas on what you think would be a cool gift idea that is also inexpensive to take back to America.
Many thanks in advance
Bex
Oh and if it helps my friend is turning 20
Many thanks in advance
Bex

Oh and if it helps my friend is turning 20