i got a seicento one for mine of ebay, it is almost identical to the Bis wheels. just a thicker bolt hole, got it to match the cinquecento alloys on my bis uses the same size tyre as the bis, just has a red wheel with a yellow 80 on it.
when i got the cinquecento wheels i had the bolts with them but they are a different thread to the 126 bolts so in the end i am using them.