Yup those are the ones. Fit perfectly and actually offer more padding and a better fit than the originals in my opinion.
I've had a set of these in black for a couple of year now. Very nice, compact headphones.
These are the pads that you are referring to I think --> https://www.amazon.co.uk/REYTID-Y45BT-Replacement-Black-Cushion/dp/B01MA3OZOJ/ref=sr_1_1?ie=UTF8&qid=1526472346&sr=8-1&keywords=akg+y45bt+ear+pads
Mine split too. (After 2yrs +). Paid £30 for new ones directly from AKG. Bit pricey. Great headphones though.
The same thing happened to me, I just found some replacements on amazon for a tenner. Wish I knew about the warranty as mine are still within it. I might try my luck with them to get a free spare set out of them. They are a 3 part pad (a bit that fits onto the speaker, a sponge and then an outside but that touches your ears) just glued together so even with careful usage this is bound to split eventually. They are easy to replace though, just slide the old ones off and slide the new ones on. A bit fiddly but easy enough job.