Is this red rot?!

[eupher61]

based on that description, It could well be, Bob. Sight unseen, I'd put a buck at 3:1 on it.

[Dan Schultz]

Yup.

[Dan Schultz]

..... Any idea of an approximate cost to replace just one outer tube? No doubt an alignment would be required as well. Or I could just pick up one of those .578 or .578/.594 Shires slides and sell my slide for cheap-ish-ish (I believe new is 800) to someone with a 1052.

You might want to just call Edwards and get a cost directly from them. I know of at least two incidents where the warranty on the parts was void unless they did the work. Sometimes it's actually cheaper to go that way.