RAF makes these, very high USA made quality, you can check stock of your choice on their website:
Handles:
Round Internal Thread Handles – RAF Electronic Hardware – the Nation's Leading Supplier of Electronic Hardware (rafhdwe.com)
Ferrules:
Handle Ferrules – RAF Electronic Hardware – the Nation's Leading Supplier of Electronic Hardware (rafhdwe.com)
Handles:
Round Internal Thread Handles – RAF Electronic Hardware – the Nation's Leading Supplier of Electronic Hardware (rafhdwe.com)
Ferrules:
Handle Ferrules – RAF Electronic Hardware – the Nation's Leading Supplier of Electronic Hardware (rafhdwe.com)