Don't get me wrong, I don't go to the dealer very much except during the warranty period. That said, the numbers you offer are not terribly out of line.

You bought the part through an aftermarket source of some sort. The dealer is not the most economic source for parts. I think everyone knows that. They are convenient, however. They have it on the shelf(usually) and they stand behind the part AND the service work. If the part you bought gives trouble, you will have to remove it, have the car down, send it off and wait for the replacement while you are walking. If the dealer installed part goes bad, they will have it in stock and replace it at no charge.

The dealer has a lot of money tied up in parts inventory. The benefit to their customer is that the part is on the premises so that they can get your car back on the road the same day(usually.)

As far as the service time goes, yes it seems high, but they have to have some time in these prices for troubleshooting. Had you driven the car in, they would have taken more than fifteen minutes to replace it. It actually took you more than fifteen minutes to replace it because you had to research, test and learn which part to replace. You can't expect them to just know what is bad without doing a little troubleshooting first.

Again, I'm not usually one to take a car that is out of warranty to the dealer, but there are reasons that their charges are what they are. In the case you describe, I don't think there was malicious intent, or a desire to "rip you off."

BTW, you obiously did a good job researching, troubleshooting and repairing your car.

Have a great weekend,