Here ya go:

http://ceriatoneforum.com/index.php?topic=4037.0

Would you please let the rest of us know what you find out and if the Mouser LED can be used? The old thread really never answered that question and my pilot light needs to be replaced too. Thanks in advance

I received the replacement LED from eBay and finally got around to making the switch.  Here's my report.
The LED version looks exactly the same on the front panel. it doesn't have a colored lens, just a colored LED. The shaft inside the chassis is longer but not so long that it hits anything.  Pulling the assembly apart reveals a 1.2k resistor in series with the LED lamp on my 12 volt DC version.  The eBay seller offered 24 volt versions which differ I imagine in the size of the series resistor only.  Typically a 5mm LED likes about 2-4V dc and about 20ma.  These values vary depending on color and output of LED.  The two issues at hand are selecting the proper size series resistor to get the proper operating current and adding a parallel diode to prevent damaging the LED from excessive reverse voltage.   Typical LEDs can take 5-6 volts backwards without damage.  We're pushing our luck with our 6.3V AC source.  Since I didn't know exactly what LED I had I did a quick test.  I used a 1N914 diode parallel to the LED but reversed in polarity, this will shunt the negative portion of the AC wave and protect the LED.  I put a 1k trim pot is series with the LED/ diode and found about 480 ohms gave me the correct current and lit up the LED nicely.  Since the closest 1/4 watt resistor I could find laying around was 330 ohms I tried that, it made the LED a little brighter but OK.  The 1/4w resistor and the 1N914 are small enough to both fit within the barrel of the new pilot light assembly.  Remember when soldering up the LED to be gentle with your soldering iron and use a heat sink since its easy to cook LEDs.  Finally product looks great from inside and outside the amp and should be maintenance free.  Hope this helps.