Re: Had an oopsie, need the name of a part.
Sirocco are long out of business, so you can't get spares through them. If there's any kind of class association, you might ask them. If there's any brand name on the mast and boom, or if you can find out who made them, you may be able to get a mast step/tabernacle from the same source.
It may be quicker simpler and cheaper to find a local machine shop, take the broken parts to them and ask them if they can fabricate new ones. The good adjustment strap, the one that didn't break, should probably also be replaced. If this boat is 30-40 years old, basically all the standing rigging parts (any turnbuckles, straps, etc.) may need replacing and while it may hurt to replace "perfectly good" parts, once they're over 20 years old they really are due for replacement no matter how good they look. The same goes for any wire/cable in the standing rigging. You just can't see the corrosion problems that develop, even in stainless steel, as it ages.