I can't find a genuine PW23Y Dell battery for my partner's XPS 13 9360...

I bought an after market one but I am frustrated that the Dell Store doesn't have them! (Or am I not searching the store correctly?)

The original is just over 3 years old and it started swelling so I had to remove it. Support state that they only last around 3 years, so why not supply them after 3 years?

If anyone knows where to get a genuine Dell one, I would appreciate it. Preferably in Australia.