Exactly right as I've been through this exact same issue in recent weeks.
I've got the same hydraulic clutch hand controls as you, which are made by V-Twin and the lever you've got is the OEM style straight lever, with the parts for the master cylinder being OEM replacement for 72-81 controls.
Unfortunately V-Twin no longer makes these hydraulic clutch hand controls or the levers for it, only brake side stuff.
But as vtwinmotors has suggested you can just use the brake parts and swap them over to the other side. The brake lever is still available brand new and all you need to do it grind off the brake switch tab and hey presto you've got a new hydraulic clutch lever. Obviously all the other parts shown such as the pivot pin, the plunger etc also all swap over from brake to clutch side without a problem.