For 8-10 mm (5/16′-3/8″) New similar Lewmar clutches are about $250. $65 or best offer.
Unlike clutches like Spinlock, the Lewmar clutches make pulling line in on a closed clutch effortless. They release easily under load. I have some on my boat and can show you the benefits. They also use the same mounting hole spacing as the Spinlock, which makes for easy replacement. The Lewmar size range is smaller than on the Spinlock, so you need to make sure they are appropriate for your line size.