The various blingalings pictured are antique Georgian collet necklaces (i.e. not for the likes of us plebs). Nerida Aylott over at Art For Interiors seems to be doing a roaring trade in replicas:
But there's something about the quality of the stones, the intense shine perhaps, that misses the mark a little.
I've had a little look on Etsy with some success:
But it's just not the same, really.
Edit: Here's a genuine one being sold at Lang Antiques, and let me be the first to say, Holy Fuckballs
Yes, it is $7,950.00