I turns out to have the same internal "guts" as the one I bought from Jaycar some years back to use while I was fixing my Weller WTCP.
That one had a base a bit like the older Wellers , but quite small.
As soon as I saw the uncalibrated knob, I knew it wasn't really temperature controlled.
I suppose you could use "weasel words" & say,"Well, you can control the temp with the knob", but that is seriously sleazy.
In my case, I thought "It is what it is" & would probably be useable, was cheap, so bought it on the "like a fuse" basis that you buy most stuff these days-----If it dies, you throw it away & get a new one!
Well, it was lousy, though I did a few jobs with it-------too hot for really small jobs, not hot enough for average work, only about one third of the control rotation gave enough heat to solder.
It felt heavy, as if it had a transformer, which could maybe be salvaged, so I decided to pop it open, only to find my "transformer" was a weight, & the same cruddy little lamp dimmer as in the OP's one was inside.
I would advise the OP to buy an old WTCP, but if they do, make sure it cycles on & off, as sometimes the Magnastat switch gets old & becomes stuck "on" making the iron run "full on" continuously.
I've never seen a Weller melt its handle though!