Thank you. You are right... Crest Spinbrush was taken over by Arm and Hammer after 2009 and all new replacement heads are now made by Arm and Hammer. In Scranton, PA..you are also right..that there are only venues with Arm and Hammer Spinbrush toothbrushes and replacement heads (my stores must have old product lines) Thus if you need new heads you would want to purchase an Arm and Hammer replacement.
One note: I did find a Feb 2012 article that suggested that these tooth brushes with the replacement heads (adult line) have a FDA warning. The FDA explained that the adult versions of the Spinbrush have removable heads that are not supposed to come off when you're using the toothbrush. But they have received numerous reports that the brush head came off, which left the metal parts underneath exposed that could cause injuries by poking the person or parts to "pop off and cause your teeth to chip, get lodged in your throat, or fly off into your eye. " The FDA warning includes these products: Spinbrush ProClean, SpinBrush ProClean Recharge, SpinBrush Pro Whitening, SpinBrush SONIC, Spinbrush SONIC Recharge, Spinbrush Swirl, Spinbrush Classic Clean, Spinbrush for Kids and the SpinBrush Replacement Heads.
So, Yes, you can buy your replacements near your home under the brand name Arm and Hammer..but looking at this warning..you may just want to get a new tooth brush. My dentist has a list of the ones that they suggest, they are always a bit more, but it sounds like they would be better if you like the spinning clean that the brush provides.
All my best, Dori