10 extra rubber backs for your pins. These backs are standard sizing, so they may fit non-RD pins too.
10 Pack Waterproof SIM Card Tray Holder Slots With Rubber Gasket Clamp For IPhone 12 Mini Pro Max Dual/Single Compatible From Ssd_kj, $6.69
Rubber Pin Backs - Rubber Clutches
Unger Power Rubber Green - Windows101
Color Rubber Pin Backs (10 Pack) – Mover & Shaker Co
Plunger and Grommet Replacement Kit 10-Pack, Enclosure Accessories and Cable Management, Structured Wiring Enclosures
LONG LASTING ADHESIVE - Sticks Great to Plastic, Metal, PVC, Engraved Name Badge, Even Cardboard CRAFT and UTILITY - Handy Jewelry Findings for Craft
10 Pack - Premium Safety Bar Pins with Adhesive Sticky Back & Metal Locking Clasp - Blank Safety Pin Backing for ID Badges, Nametags, Ribbons, and
Rubber Stopper with 3/8in Hole - Available in Sizes #2 to #13 - Olive Wood Brewing & Craft Co
O-ring White for 2.2mm Ball (10 Pack)
Rubber Pin Backs - Rubber Clutches
Yellow Rubber Pin Backs [10] – Nerdpins
10-50 BUTTERFLY / RUBBER / LOCKING LAPEL PIN BACK CLUTCH CLASP FASTENER
AgraLink Cat1 Top Link Pin 5-1/2