Yes the 2 peice collar insert is the current replacement, there's still plenty of the older single peice inserts around, just got to search around for them.

I think this is what you're after: https://outwestcoffee.com.au/product/bre...

Hi Isabela, i found a couple on ebay still:

(USA) https://www.ebay.com/itm/156470279309?_t...

(Australia) https://www.ebay.com/itm/135067650222?_t...

Hope you're able to get this fixed!