Will, thanks for the text of Rev. 7. It must be the text I have been searching for, as so far this is the only listing of the tribes that has Dan missing, as well as Ephriam, one of Joseph's sons, and "birthright replacement heir", Ephriam.
I see that that the scripture is talking about the 144,000, rather than the gates of the New Jerusalem. This listing seems a bit unusual as Joseph as well as his other son, and "birthright replacement heir", Manasses are both listed. Usually if Joseph is listed his two sons aren't as they would be included under him.
When the tribes split, Judah and Benjamin were the two tribes together along with the Levites, Scripture appears to refer to them as the nation of Judah or at times Jacob.
The 10 tribes were referred to in Scripture as Israel or Ephraim.
Revelation 7 (King James Version)
4And I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand of all the tribes of the children of Israel.
5Of the tribe of Juda were sealed twelve thousand. Of the tribe of Reuben were sealed twelve thousand. Of the tribe of Gad were sealed twelve thousand.
6Of the tribe of Aser were sealed twelve thousand. Of the tribe of Nephthalim were sealed twelve thousand. Of the tribe of Manasses were sealed twelve thousand.
7Of the tribe of Simeon were sealed twelve thousand. Of the tribe of Levi were sealed twelve thousand. Of the tribe of Issachar were sealed twelve thousand.
8Of the tribe of Zabulon were sealed twelve thousand. Of the tribe of Joseph were sealed twelve thousand. Of the tribe of Benjamin were sealed twelve thousand.
9After this I beheld, and, lo, a great multitude, which no man could number, of all nations, and kindreds, and people, and tongues, stood before the throne, and before the Lamb, clothed with white robes, and palms in their hands;
10And cried with a loud voice, saying, Salvation to our God which sitteth upon the throne, and unto the Lamb.
11And all the angels stood round about the throne, and about the elders and the four beasts, and fell before the throne on their faces, and worshipped God,
12Saying, Amen: Blessing, and glory, and wisdom, and thanksgiving, and honour, and power, and might, be unto our God for ever and ever. Amen.
13And one of the elders answered, saying unto me, What are these which are arrayed in white robes? and whence came they?
14And I said unto him, Sir, thou knowest. And he said to me, These are they which came out of great tribulation, and have washed their robes, and made them white in the blood of the Lamb.
for this link that includes Chapter 50.