Did Harry have a Horcrux in OOP?

[vantelvanna]

No: HPFGUIDX 150872

OK I could have missed this but please if not let me know what you 
think.
I am rereading OOP, but on audio book,   and  in the middle of 
supper a line hit me like a TON of bricks.. So here is my thought
.
In HP,  Harry and Dumbledore get the locket that is a fake 
Horcrux right? and it have a note with the initals R. A(?).B. on it.

Well in OOP Harry is talking to Sirius about the family tree tapestry 
and they talk about he brother Regulus Black (R. ?. B.) and later in 
the chapter when they (the kids Mrs. Weasley and Sirius) are cleaning 
there is a "also a heavy locket that none of them could open" 
so do 
you think that this could be the "REAL" locket? The initials  could 
match.  We don`t find out Regulus' middle name so it could be? We know 
he was a DE and he tried to get out
.

What do you think? Could Harry have had one of the Horcruxes in his 
hand in OOP?

Vanna