I recently acquired an old Bear tape on quiver from the 50's and the rubber arrow grippers are very stiff and hard, is there anything you can put on the rubber to make it functional again?
 

Probably easiest to just replace it...

http://www.3riversarchery.com/Bear+4-Arrow+Gripper_i3590_baseitem.html

Jonathan

I've softened them with Armour all if they're not too far gone. Soak them several times a couple hours apart.

There used to be a product call Ruglyde. You could get it at automotive stores.  It is the same stuff you see tire changers brush all around the beads of tires when mounting them to keep them pliable and soft.  Not sure if it is still available, and it came in gallon quantities.  But it would keep any rubber from cracking and splitting or drying out.