Stop! Never buy a 2nd hand claimed Mikimoto without some kind of proof.
At least look at the clasp look on the back for a seashell with an M in it. This is a fine piece, It is obvoiusly from some place like saks, but get some proof before you put out the money. If this piece has the right clasp, I would take the chance it isn't fake. Is that a bracelet? If not, look for that M stamped somewhere.
I don't not think you will find equivalents for pricing purposes, so don't get carried away. for the style and the gold, with no proof, not over $1,200 and that is high for going pearl bracelets with no proof except the Saks box. With proof, at least double that. If you love it, buy it, but do not think you will be able to sell it for much more than the numbers I gave here, probably less.