You will require an Italian threaded bottom bracket. Time to search ebay for a Campagnolo unit. Otherwise, you need to measure the one you have to begin to reference what you need. A Phil Wood would be good, but not cheap, one from SKF, (compass bicycles) You might find one from Velo Orange... each has a few to choose from, time for a measuring caliper.

Basically, from a width perspective Italian is no wider than English Overall, the difference is the width of the BB shell, 70 mm for Italian 68 for all others in this time frame. Yes, there is a bit of referencing to do regarding tapers.