I have a couple Rat Shack 60 watt temp-controlled LCD-display soldering stations:
They're actually pretty nice and work well. The irons take a replacement
4-wire heater that's readily available fro Amazon.
They take an odd tip though, it's not a Weller external screw-base type. It's not a solid-type. It's not the short-base hollow-type with internal threads that my temp-controlled Weller uses, "ETA" I think this is called. It's a long-base hollow with no threads, slightly larger diameter hole than the ETA-type, that the heating element slides into. Is there a name for that type to look up when looking for tip sets/replacements?