Hi there,
Sure you can do that. The issue is that it's not current proof. Why do you have a need to tell someone you had Hepatitis C anyway? You don't have it now. There wouldn't be a reason to provide proof only if it interfered with employment in some way. Like pre employment blood test. If this was required you would have to provide a current RNA Hepatitis C viral load test.
Only that test would prove you currently don't have hepatitis C. As you should know, you will test positive for Hep C antibodies for the rest of your life. This means you either have Hep C or were exposed at one time. That's why your proof... will only come from a current viral load test.
Hope this is helpful