That is the same part # that I see listed on Bike Bandit for the 2006 Classic as well as all Rocket III's and Roadsters from 2005 through 2016. All list at $199.95.
As John Ward notes the accuracy can be all over the map depending on the sender unit "calibration" in the tank. I have that same gauge and in itself I think it is fine but it depends on the sender gizmo in the tank. The float arm needs to be tweaked to properly represent the true fuel level as reflected on the gauge. Someone on the forum has done a good walk through on what is involved in the bending of the float arm to achieve a good reading on your gauge. Like John Ward's comment......my gauge reads empty and light comes on when I still have half a tank of gas. It helps to get in the habit of using your odometer to know when a fill up is urgently needed. Someday I might try calibrating the sender.
PS When I bought my bike with 20,000 miles the gauge did not show any reading and the light never lit. I replaced the sender with a new unit and then the gauge and light worked......not accurately but it worked. I can't be sure the old sender needed to be replaced. If I had fiddled with it maybe it would have come to life.
By the way if you do not have the clock that matches the fuel gauge you should get that too.....to have a properly balanced appearance on your bars

......funny thing.....my clock is always dead on accurate, but it is a bugger to re-set the time with it's finicky little rubber push button after you have disconnected the battery power for whatever reason.