My 8 year old son has recently got into coin collecting (he's currently hunting for all the circulating commemorative £2, 50p and 10p coins). However, he's also developing an interest in ancient British history and I'd really like to get him either an authentic Celtic or Roman silver coin for Christmas. However, I have absolutely no idea where to find a reputable dealer in ancients (my experience lies squarely in modern bullion). Would anyone be able to point me in the right direction? Not looking to pay a huge amount as he'll no doubt take it into school for show-and-tell, so I expect we're looking at Roman here rather than Celtic.
Thanks in advance for any help you can offer.