Complex sentence: Some Jewish Pagan groups, such as the Order of the Temple of Astarte, have been around since the 1970s, and may be offshoots of either Reconstructionist Judaism, Neopaganism or both.
Split into simpler sentences: Some Jewish Pagan groups, such as the Order of the Temple of Astarte, have been around since the 1970s. It is considered that many Jewish Pagan groups are offshoots of either Reconstructionist Judaism, Neopaganism or both.