At the end of last week, the Huawei Mate SE was listed on both Amazon and B&H Photo Video. Even more, it also got an official page on Huawei's website. However, all these listings of the rebranded Huawei Honor 7X were removed since then. The US$249.99 Mate SE apparently will come in grey and gold, but now it looks like we have to wait for it to get a proper release.
https://www.notebookcheck.net/Unlocked-Huawei-Honor-7X-apparently-being-rebranded-as-Mate-SE-in-the-US.284840.0.html