I have seen quite a few Fiat 500's at shows around the country over the years.
There is (was?) also a specialist based in Donadea, Co Kildare a few years ago (I have a ph no somewhere. I'll have a look for it at the weekend when I'm home).
Post a message over in the Classic's section of boards.ie......lots of info there on all sorts of classic's!
regards,
Silvera.