Lionel Smoke Unit Availability

Not a surprise at all.  Apparently, from what  I understand, many of the spare parts are teardowns of new product or returns.  The Chinese apparently don't sell "spare parts", just completed product.  So, when they run out of a particular part, it's simply no longer available.  You'll see a ton of parts for various products listed as "not available".

I adapt whatever smoke unit is available to use in upgrades.  I've used a lot of MTH smoke units as they're fairly compact and very good smokers.

I didn't know that. I would have assume that there was an assembly operation for all the parts so it would make sense to just keep making smoke units. I guess it makes more sense if the suppliers only sell completed units and there are no parts.