I'd do exactly what you just did. Send him an email and NICELY tell him that there are a few parts missing. Tell him you will make an inventory of the missing parts in the next day or so.

Then wait for him to respond. Give him at least 48hrs to read his email and get back to you.

If he doesn't respond, then call him. Be nice. Tell him there are a few missing parts and ask him if he could send them to you.