[Polar1]

Yes, I know which tips you're talking about, the ones with the green core and the foam around it. They are supposed to improve the sound isolation and they are quite expensive indeed. I don't know how you can be sure that they are genuine though.

 

[Sound Eq]

  Yes, I know which tips you're talking about, the ones with the green core and the foam around it. They are supposed to improve the sound isolation and they are quite expensive indeed. I don't know how you can be sure that they are genuine though.

i know i have 2 grean ones filled with foam, but look different from inside and feel different, one the foam is more gooee and tightly attched to the silicon wall and edges, and the other the foam is a bit losser and fluffier and is not attached to the wall and edges of the silicon
 
i am looking for the one that is more gooee and attched firmly to the wall of the silicon even if its a knock off as it feels way better
 
anyone else can chime in

 

[benthezhu]

Thought I lost mine, but ended up finding them in a corner of my desk. However, I did end up taking the time to call CS, and they redirected me to Encompass after looking up the item ID. I have been told by the rep that this item is an exact match to the Noise Isolation tip, because they have stopped manufacturing them (which apparently is true). 
https://sony.encompass.com/item/10222551/Sony/4-259-055-03/Piece(m)_Ni_Ear
 
The item number for Encompass is 4-259-055-03
A decent alternative for the current ones available on eBay from Japan that fluctuate in stock to potentially try out

 

[webvan]

OK, problem solved and at a cost of 0$ too !
Not my tutorial, it's from : https://www.reddit.com/r/headphones/comments/3f3nb4/where_to_get_the_tiny_foamfilled_eartips_for_my/

I used a 4mm hole punch.