Up for sale here is this NOS unused vintage dual concentric quad (4-section) potentiometer, from the 1960s or 1970s and probably Made in Japan. This is an interesting one--it has two linear taper 500k sections and two linear taper 250k sections. Only two sections have loudness taps, I believe those are the 250k sections. It may need a little Deoxit but will work fine. This is a dual concentric pot, so there is an outer and an inner shaft. The shafts are about 8mm diameter and about 6mm diameter (inner). Please see my pictures for details and dimensions.
US shipping and handling is $5, and international is $18. All my small parts are set up for combined shipping, so just use the "add to cart" feature and then check out all at once, and it will combine shipping. If you have any questions, please ask.
I have more vintage pots and other vintage electronics listed--feel free to take a look!