Now, kids. Behave! You guys are so bad.
The bottle looks like it could be the work of either Seguso AV or Archimede Seguso. Archimede did a lot of the threaded atomizers. AV probably did, too, but I'm not as familiar with their bottles. These companies would be good ones to start a search. I have an Italian auction house catalog from a few years ago. The attributions are very good. I was impressed with the number of sommerso pieces the companies produced. Most of them were very simple, but well done. Your bottle seems to fit the description from what the pictures show. The colors look like something the Segusos would have done.