My aft of mast Windex broke (not the Raymarine little windex with the anemometer). The tail fell off (bird landing?). Any info on replacement that will screw in with the same threads? Size suggestions? On Defender, I see a Davis Instruments WindTrak 15 Wind Indicator - 3150. Anybody know if this is compatible with the existing mount on my 2002 C320? There's also a Schaefer Hawk Apparent Wind Indicator but it's only 10" long, for boats up to eight meters (ours is more).