Bnei Tzion is an Israeli siddur published in 1996 by Sinai Publishing in Tel Aviv. It's a Sephardi siddur but has some interesting variants (e.g., very similar Havdalah to Ashkenazi practice). I'm looking to find out the specific Sephardic group(s) that use this siddur.
I bought a "pocket edition" of Sidur Bnei Tzion from a bookstore in Paris in 2006; it is almost identical in order and contents (although more reduced) to a Sidur used by Congregation Beth-El of Rio de Janeiro (Brazil). Their Sidur, called "Siddur Matzliach Melamed" was compiled by Rabbi Meir Matzliach Melamed for a Portuguese/Hebrew Edition in the 1960's. He was of Turkish descent, so I believe those are mostly Sefaradim of Levantine origins in General.
The siddur with same name is used by Jews in Serbia, Sefardi mostly. Today we have new edition but it is based on Serbian edition from the beginning of 20th century.