Try Familysearch Beta, there's no "African American" marriage records for North Carolina, but there are marriage records for the state, 1759 to 1959.

I read your post over on the Surnames Forum, I almost overlooked the search results at familysearch because of the names being off a little (Amos Obrien instead of Amos Bryan; and Affie Solone instead of Effie Selone).

Groom's Name: Amos Obrien
Groom's Birth Date: 1815
Groom's Birthplace:
Groom's Age: 59
Bride's Name: Affie Solone
Bride's Birth Date: 1844
Bride's Birthplace:
Bride's Age: 30
Marriage Date: 16 Mar 1874
Marriage Place: Woodbridge, Craven, North Carolina
Groom's Father's Name:
Groom's Mother's Name:
Bride's Father's Name:
Bride's Mother's Name:
Groom's Race: Black
Groom's Marital Status:
Groom's Previous Wife's Name:
Bride's Race: Black
Bride's Marital Status:
Bride's Previous Husband's Name:
Indexing Project (Batch) Number: M01314-6
System Origin: North Carolina-EASy
Source Film Number: 288298
Reference Number: Pg. 125-126

http://tinyurl.com/2cq53n4

Groom's Name: George Bryan
Groom's Birth Date:
Groom's Birthplace:
Groom's Age:
Bride's Name: Matilda Salone
Bride's Birth Date:
Bride's Birthplace:
Bride's Age:
Marriage Date: 17 Mar 1872
Marriage Place: Raleigh, Craven, North Carolina
Groom's Father's Name: Amos Bryan
Groom's Mother's Name: Janette
Bride's Father's Name: Edward Salone
Bride's Mother's Name: Hannah
Groom's Race:
Groom's Marital Status:
Groom's Previous Wife's Name:
Bride's Race:
Bride's Marital Status:
Bride's Previous Husband's Name:
Indexing Project (Batch) Number: M01315-2
System Origin: North Carolina-EASy
Source Film Number: 288298
Reference Number: Pg. 23

http://tinyurl.com/2bkfznz

It looks like Amos and George are father and son, and Amos was married previously.

Looking at the 1870 census for New Bern, NC, I see Amos Bryan and wife Jennett (the mother of George) at door #106, next door is another Bryan family, and then two doors down there is Effa/Effie Selone with a Caroline (6) Emma? J (2) and a Emmaline (9 months).

Two doors down is Matilda Selone with a Bettie C (1 or 6) and Eliza (12)

With them not living in the same home, it is hard to tell whether they are sisters or not. According to the marriage record, Matilda's parents are Edward Selone and Hannah.

With it being so close to the end of slavery, it could be they just had the same slave owner or used the same last name coincidently. I would look more into it, the marriage record for Effie doesn't give parents names, maybe it wasn't included on the record or maybe the indexer "forgot" to index it.

Have you found a death certificate for Effie? May give parents.

Have you found a marriage record for your 3rd great grandmother? Have you found her in census? Have you found a death certificate for her?

Hope this helps