Hello I will help you with your question,
That seems reasonable if that includes labor and the crank and bearings. The list is 28.8 hours labor and $1716 for the crank so your estimate is about 1/4 of the list price.
Why is the crank being replaced?
That makes a huge difference.
If they only replace the crank sensor the timing belt will be removed along with the other belts on the front of the engine so if any of the belts are worn it is a good time to replace them. With a $1275 estimate I suspect that other work is to be performed at the same time though.
The sensor list price is $80 and the time required to replace is 3.0 hours so at $100 per hour labor and 1 hour to diagnose it the charge should be $480 plus shop fees and taxes.
I would be very sure about what work is being done and if it is just the sensor and the time to diagnose ask what the costs break down to.
Let me know what I can do to help and please ask any questions you have about this