For your consideration, we offer up a high-voltage, 14-31 pF variable capacitor. The manufacturer is unknown but the model number appears to be T-7660443-8. The capacitor is in good condition with some scratches, dirt and wear. A 0.25 inch extends about an inch from the body of the unit. The shaft turns easily and exhibits no slippage. I measured the capcitance with an Agilent U1731A Handheld LCR meter (see photos). The distance between plates of opposite polarity is abut 2.5 mm.

The variable capacitor, shown in the photos, is the only item included in this listing. The photos were taken on a 1 cm grid. I will combine multiple items together to reduce shipping costs and will mail one or two business days after receiving cleared payment. 

Questions are welcome. Thanks for stopping by!