Do they exist?
Can I work 30-40 hours/week with no call, no weekends, no overnights, no holidays with the trade-off being a significantly lower salary, i.e. ~$180-250K/year ?
I know jobs like this exist in other specialties (like anesthesiology), but what about rads?
12 years ago I could have written your post myself.... Maybe I should check my post history. I probably did have a similar post. I too went to med school wanting to eventually end up in a field that was chill.... At least with the ability to work less even if I made less. I wanted to do oncology... And once asked an oncologist the same question your asking. He kind of laughed at me. Fortunately I chose rads. Dodged a bullet... Kind of.
Rads is busy with its own stressors, which would be a whole other post. Way better than many other specialties though. It is possible to get a part time job like your describing without much trouble. You just might not get your first choice of location. Doing this early in your career would be risky based on how it would be viewed by other rads (like if you needed to find a new job), but I don't think it's that big of a deal if you just explain it away due to family reasons/obligations/etc.
As someone else has already mentioned - Telerads would be an option. Probably the easiest, but a last resort. It pays ****, you have to read a ton of studies quickly, and most of the shifts will be at night. It's also not a good professional move in your early career. You will lose procedural and advanced imaging skills.
There are many large regional groups that would hire for an employee position (as opposed to partnership tract). Especially now that the market is opening up. You'll just have to be honest up front about what you want.
Probably the best option that I've heard of would be an ER job that is afternoon/early nights with shifts between 4pm-1am. These are usually at larger hospitals that are academic or semi academic. They'll be 1 week on/2 weeks off or will be like 10-15 shifts per month (They'll have a separate work pool for 10pm-7am shifts which you opt out of). The hours aren't great... But you work less than half the month and get paid avg radiology salary (not part time salary). These jobs usually require that you know the right person or you just get lucky.
There's also VA jobs. These are 8-5pm, 1 hr lunch, m-f, no weekend and no call.... And low volume. These are easier to get than the last type but pay a little less. This would also be a good option, although its not necessarily the best career move early on (rads in private practice often wonder "what's wrong" with the radiologist that had to settle for one of these jobs- "why couldn't they hack it in private practice"). Again, I don't think this is that big of a deal if you explain it away based on family obligations/desired location/etc.
As to what subspecialty? Just don't do IR. They are stuck doing more overnight procedural call. Neuro may help you land one of those sweet ER jobs, but they can also be stuck doing additional call depending on the group. My current group does have part time mam readers, but I'm not sure that is based on their subspecialty as much as it is on that they are moms in duel income households with young kids or close to retirement.
I ended up taking a standard PP job. It's mostly 8-5pm with a few weekends and a few weeks of nights per year. But my group is structured in such a way /is large enough that I can cut back and make less which I likely will do eventually (E.g. tell them im done with nights and weekends). I averaged 40hrs/week last year based on total hours worked / number of weeks worked. It ranges from about 27-63 hrs/week depending on my rotation.