****Update 4/20/2010****
I was able to retrofit the 3.3V regulator with the MCP1826S-3302E/AB. It is pin compatible and spec'd to -40C. I got a good 3.3V light, and the LE went through its test sequence with no apparent issues. I did notice looking at the specs again that the max input voltage is 6V, but should not be a problem since the input is from the 5V regulator. It does cost almost twice as much as the original regulator, but it is in stock.
Disclaimer: This substitution has not been approved or recommended by RJ.
****End Update****