Hiya
I get all my collars (and for the kitten packs) here...
They are the breakaway types
very soft
with a bell
She handmakes them! - and you only have to pay postage for one - no matter how many you buy! She has a fair few in the clearance section too in very funky patterns. I also know that if there is a particular patter you like in her small dog collars she will make a cat/kitten collar to order for you in that fabric (no extra cost!).
eBay Store - HotDogsCoolCats: Mini 7-11, X Small 7-11, Teacup 6-8
I think its somewhere like £2.70 for a unique collar and the postage is about £1.80 (like i said that doesnt change whether you buy 1 or 30 collars). I always have a stock of them here as i foster pregnant rescue cats, so new cats get their own collar and the kittens go to their new homes with a kitten pack including a brand new kitten collar!
hth xx