I ordered mine from Partzilla.com. They have good prices and I got it as fast as my local dealer could get it.
Here's a link to the Yamaha section of Partzilla's website. Pick your year and GO:
You'll find your sending unit in the Electrical 1 section, NOT the fuel tank section.
Here it is for the 2002 Silverado, which should be the same for all 1600's if I'm not mistaken. You want part #30 for $76.40: