Anyone know where to purchase cat claw softener (not the adhesive claw covers)?

I've never heard of such a thing and would not advise using it. What happens when the nails get soft? The cat can't scratch its scratching posts and could injure the vein. Try buying cat nail trimmers and see if your cat will allow you to trim the sharp tips of the nails. Put the cat in your lap, gently squeeze the paw to expose the nails, and cut off the curved tip, avoiding cutting too close to the vein. Offer the cat treats. Try a nail or two at a time until your cat gets used to it. You could have someone help you. One person could scruff the cat (loose skin on the back of the neck) while the other trims the nails.