Just found a source for an inexpensive water temperature LCD with metal probe.
Purchased one at $16.95 + $6.90 shipping.
Temperature specs are Range: -50 to 150C, Resolution: 0.1C, Accuracy: +/- 1C. Mounting hole cutout dims are 2.25-in. x 1-in. Color is black, battery powered.
Note, web site does not show their entire stock/selection.
Link as follows:
http://www.techinstrument.com/PanelWallMountindex.html