Water pressure gauge question?

My 2003 v-max 225 water pressure gauge is resting at 10lbs and reading too high when running. Is there any way too calibrate these or do i have too buy a new one? Also my gauges are silver, where can you get the replacements? http://www.bassboatcentral.com/smileys/doh.gif

Looks like water froze inside... I have replaced 3 water pressure gauges in my boat from the same exact thing.. http://www.bassboatcentral.com/smileys/doh.gif