already posted this on another forum so hope you dont mind the link, i posted 1 shot so u can see. This was a standard black SGS with the 2 parts replaced, its so nice
By the way I found THIS on eBay. Not sure if it's worth it. $32 and he even says it's "Not Original but very very good quality".
but it's up to you.
-- EDIT --
There's also http://stellatech.com
they seem to be selling every spare part including this one and it's quite cheaper and probably original (though it's out of stock ATM). I think I'll try this one.