I think it may be the titleist balata, but I'm also not sure whether they make them any more.
You can search places like ebay, because they sell them very cheap, and they will be collectors items in a few years, as they are rare.
They might be illegal, but I don't think so.
I only have 1 and I'm keeping it.
You may want to try maxfli noodles. I tried them and they are great!
Or the final option is the prov1, but thats expensive. Prov1x Is hard, no matter what some people say(I think)
Hope I helped (btw, Sorry about saying Ithink alot)
Edited later:
Hi to everyone out there. The prov1x does NOT spin more. It is one of the harder balls out there, not softer!
The prov1 is softer and can spin. Trust me, don't go prov1x!