A nice vintage find. What name is stamped on the hubs? Is it Campagnolo? Steel or alloy rims? If the wheels are original you can remove a couple of the cone locknuts and look for a date stamped on them which would assist in the dating process. However if there is sufficient serial no. data available I would go with that first for dating your Olmo. The RD looks like a replacement (Is the shifter lever on the down tube bent?) I'll bet it had a Gran Sport as original equipment. Definitely an early 60's Olmo.