Though the temple is mentioned many times throughout the Apocalypse, the only reference in the entire prophecy which could even remotely be taken to refer to the earthly Temple in Jerusalem is in the beginning of chapter 11. Generally, temple references in the Revelation have everything to do with God's abode in heaven and nothing to do with the earth or Jerusalem. However, since both Temples are mentioned in chapter 11 (see 11:19), I think it is quite clear that the earlier reference is definitely to the earthly Temple in Jerusalem. Does that help date the prophecy in anyway? No, I don't think so.
The language of Temple measuring in chapter 11 is reminiscent of Ezekiel's, which was written many years before. That prophecy was made 14 years after the destruction of the first Temple (586 BCE) during the exile of the Jewish people to Babylon. Though Ezekiel's descriptions are vivid, down to measurement and dimensions, there was no such Temple in Jerusalem when he wrote it--not then, not since (even though a Temple was built by Zerubbabel in Jerusalem and remodeled by Herod the Great). In other words, by biblical precedent, a detailed reference to a Temple in Jerusalem in biblical prophecy is not proof whatsoever that such a Temple existed at the time of its writing.
Since all other references to the Temple in the Revelation clearly refer to the heavenly Temple, there is nothing about any Temple reference which could justifiably be used to infer that the earthly Temple was still standing because of those references. In fact, at the end of the prophecy, perhaps as what could have been an ameliorating salve to those concerned about the earlier loss of the earthly Temple, we are told that no Temple is necessary in the grand scheme of things. I would think that the last treatment of the Temple in the work would be at least as significant in pointing to a post-destruction dating of Revelation, as the middle treatment could be in suggesting a pre-destruction dating.
The language of Temple measuring in chapter 11 is reminiscent of Ezekiel's, which was written many years before. That prophecy was made 14 years after the destruction of the first Temple (586 BCE) during the exile of the Jewish people to Babylon. Though Ezekiel's descriptions are vivid, down to measurement and dimensions, there was no such Temple in Jerusalem when he wrote it--not then, not since (even though a Temple was built by Zerubbabel in Jerusalem and remodeled by Herod the Great). In other words, by biblical precedent, a detailed reference to a Temple in Jerusalem in biblical prophecy is not proof whatsoever that such a Temple existed at the time of its writing.
Since all other references to the Temple in the Revelation clearly refer to the heavenly Temple, there is nothing about any Temple reference which could justifiably be used to infer that the earthly Temple was still standing because of those references. In fact, at the end of the prophecy, perhaps as what could have been an ameliorating salve to those concerned about the earlier loss of the earthly Temple, we are told that no Temple is necessary in the grand scheme of things. I would think that the last treatment of the Temple in the work would be at least as significant in pointing to a post-destruction dating of Revelation, as the middle treatment could be in suggesting a pre-destruction dating.