Design for Nintendo Switch.
eBay
2pcs Nintendo NS Switch/Lite/OLED Thumb Grip Cap for Joy Con Switch Controller Joystick Cap Silicone Rubber Thumb Grip Cap
Aliexpress UK
Price is for a single part. Parts available Genuine parts, taken from Nintendo Joy-Con set. Wriststrap wrist band handle. Appears to be in very good condition. I do not know if it works.
eBay
GeekShare Cat Ear Grips Enhancer for Nintendo Switch / Switch OLED Joy-Con Controllers with 2PCS Thumb Grips,Pink & Blue
Aliexpress UK
Local pick up is not available.
eBay
Skull & Co. JoyGrip JoyCon, mango de carga, soporte, cargador para Nintendo Switch y Switch OLED Joy-Con Controller
Aliexpress UK
eBay
2PCS Steering Wheel for Nintendo Switch 2 Joy Con Controller Switch Joycon 2 Racing Wheel Hand Grip for Mario Kart 8 Deluxe
Aliexpress UK
eBay
For Nintendo for Switch 2 Grip with Stand Handle Controller Holder Anti Slip Handheld Case for Switch 2 Game Console Accessories
Aliexpress UK
Switch console not included.
eBay
FUNLAB 4 PCS Cute Silicone Stick Cover Switch Thumb Grips Joystick Caps For Nintendo Switch/OLED/Lite Controller Accessories
Aliexpress UK
Compatible Platform: for Nintendo for Switch. Due to the different monitor and light effect, the actual colour of the item might be slightly different from the colour showed on the pictures.
eBay
Mobapad M6 HD Bluetooth Controller Hall Joystick With NFC/Wake up Support For Nintendo Switch/Switch Oled M6HD Gemini2 Gamepad
Aliexpress UK
The 360 degree esports joystick has no dead corners, and is responsive, with international quality. Six axis tactile function with high precision, low delay, and precise positioning. Both the left and right handles independently support TURBO combo without fighting hand speed, making it easy to win.
eBay
8BitDo Ultimate 2 Bluetooth Controller for Nintendo Switch / Switch 2,PC,Windows TMR Joysticks with Charging Dock
Aliexpress UK