You can easily make one --- there is nothing special about the foot switch for these model(s).
Basically, the Channel/EQ use the front jack using a TRS cable, Sleve is ground for both, each connect through the SPST Latching switch then through a LED, one to the Tip, and one to the Ring. The Reverb is pretty much the same, although, I cant remember if the Reverb supports an LED, it should, I will confirm for you tonight.
PM, and I'll draw up a schematic, and give you part numbers for what ever local electronics store you live near. --- But it should be really cheap, and really easy to make.