Good looking stuff. I can understand why you want to restore it.
For all I know Peelaway may contain things other than sodium hydroxide to lift emulsion but, if it doesn't work, you could try one of the new Eco strippers
place will have their own version. "French polish suppliers" in yellow pages? As a cheap d-i-y experiment you could try loading a section with thick wallpaper paste and leaving it overnight. The soaking action plus gravity might pull the top layer off. Whatever you use it's gonna be a labour of love I fear :-)