This is my first laugh of the day- "It's been gone three hours and I miss it already'.
My guess is $40.
Edited to add: Now I have read all of the responses I think I am low. Mine was just in for general service and it came back making a noise. (cost $90 plus tax) I took it back right away. It was something with the "hook" and there was "no charge". This was Byrne's sewing in New Britain, PA. This is my favorite shop.