I have an old pair of Field and Stream brand Thinsulate convertible mitten/fingerless gloves. The fleece shell is snug, the textured vinyl grip extends to the full inside of the covered thumb (only 4 fingers uncover), and the velcro keeps the mitt thing from flapping. The mitt even has a pouch for warmer packets, which are prob only needed when waiting for Bambi...
They take a bit off the touch putts, but nothing like numb fingers when playing in 20deg on the windy shores of Erie at the Euclid course (which has a bar across the street from the 12th tee).
About $10 at a local sports store iirc.
Jokeri, Wasp, Fuse, Timberwolf, PD, Predator