I forgot all about the sashiko thimbles!
The one we carry at A Threaded Needle is the Olympus brand leather sashiko thimble.
It has an elastic tie at the back for adjustability, and indentations on the pad to keep your needle from slipping.
Its hard to change the way you do things once you start so I probably never will use a thimble, but I imagine it would be easier on your fingers if you pushed the needle through, instead of pulling as I do.
Also, I gave it a try just now, and find I can put 4 or 5 inches of stitching on my needle at once if I am using the thimble to push the needle through. I can't pull that many stitches at once, so for long straight sashiko lines it would speed up the stitching quite a bit.
You wear a sashiko thimble pushed to the base of your second finger as shown. I have fatter fingers than most women so I would want to loosen the knot in the elastic at the back. For most of you, I think the width it comes in will fit comfortably.
To use the thimble gather your stitches on your needle, rest the end of the needle against the thimble and push.
Huh! I just noticed I have it on the wrong finger in this photo! Take a look at the package image above- they show it on the finger next to the index finger!
Owner A threaded Needle