Historically, I would classify the Westerner, the "meat grill" custom and the Chromoveil custom as limited editions. Same for the Penthouse, Fireplace kettle and even Galley Qs. I would guess the Woodard carts were pretty low volume too. But that's just my opinion. All were catalog items at one point, so maybe that nixes the idea of a LE.
I'm not aware of anything they marketed in the modern era (letter-code kettles and up) as limited edition, but it's possible. You know what they say: anything sold as a limited edition collectible will only be limited to the number of people willing to buy it, and will never be collectible.