The Japanese models are not 22.5" scale, they are 24" like a standard Mustang. If scale length is your concern, then a standard 24" scale Mustang will feel very similar to a Les Paul, so you don’t even need a Mustang. You can choose either one and get a similar range of fretboard stretch.
If you want a smaller scale length, and a smaller body, then you want a Musicmaster, Duo-Sonic, or “student scale” Mustang from the '60s. You can identify them because the last fret on the board will have the dot inlay. If the last fret does not have a dot, then it’s 24", not 22.5".
You can find them used for between $700 and $2000 on Reverb.
Even before fixing noise issues and replacing pickups, the bridge pickup and pots are not the original ones, and the toggle switch has been added, is it from you or you bought it with these mods ?
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