Wishbone Brooch Emerald Green Silvertone

Vintage costume jewelry wishbone pin with a lot of markings that are not clear. At first, I identified this as being a stamped Coro. But, in my internet search I haven't found a Coro that looks like this. There were a couple of emerald green crystal rhinestones that I replaced because they had fallen out. The yellowish-white pearls in the flowers are from the original design when I got this in some estate jewelry. Emerald Green is the May birthstone. Good working condition, nothing is loose or mechanically flawed.