I think there are several polyester (plastic ) bowling balls with a good weightblock and some already mentioned.
I have the clear Amulet and the black XXXL.
there was also the clear Wolf, I believe it was RG who had one with a Grenade in it and I don't know the core strength of the clear Ebonite Skull ball (original) but Pchee2 used that as a strike ball quite a bit and carry was great. I'm sure there were others but some of the older urethanes worked just as well. The pink Hammer comes to mind.
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Nicanor (Ten On The Deck)