I was shocked - and somewhat amused - when speaking with a friend (irish - called himself a big fat Mick) from Brooklyn and he informed me that they called them “guinea vests.”
That’s a new one to me. 
I don’t think “guinea” is used much around here (though I am familiar with the word). At least in my era (80s), it was “dago” and “wop” for the Chicago area, if we’re using pejorative slang. Heck, I don’t think I even realized that “dago tee” parsed into “dago” + “tee.” As a kid, I just kind of ran it together in my head as “daygotee” and assumed that’s what were called. I remember one of my friend’s older neighbors going off one day about the “krauts” in the early 90s, and it just sounded so anachronistic and funny to me, as I’ve never heard anyone use that slur unironically. (Or, frankly, not even ironically. Even “mick” has a bit of that weird, old-timeness to it, though not as much as “kraut” or “limey.”)