It seems like a great price to me, especially including parts.

Think about it this way...
If he changed your oil with Mobil1, its $20 in oil and another $5 for the filter. So with tax and change, etc, he probably changed your oil for $6-$7.

If the Tbelt and WP cost you $200 total, and the oil was $33, he did the labor for less than $400. Thats including the valve adjustment (~$70), gaskets and labor. Sounds good to me.