They (all clips) are more or less universal on the E Series lights. Make sure when you change it you also change out the small black piece of plastic. You can contact SF and they will send you a new one for free. They don't always have the two way clip available. In that case you have to buy it. But no big deal. $50 sounds like a good deal. Also, there are some ways to remove the old clip. I use string. It just slips in and out. With practice it is easy. I just caution you that after you do it a few times, it will wear out the small black piece of plastic.
I have added a tiny tiny drop of gel super glue or 5 min epoxy to worn out ones to make them snug again. But, I am not glueing them in, just put a drop on it, let it dry, then reinstall as normal.