Research experience and research fit are very important. Doing a thesis is great, and you say you have other research experience. Have you read about the faculty at the programs you mentioned to determine if their research is a fit? The “top schools” in Social Psychology, for example, may not have faculty doing research that suits you - and that alone could hurt your chances for admission. The best way to find faculty doing research that interests you is to read articles in your area of focus (such as what you’re doing for your thesis) and see where the authors work. For example, you may find yourself excited to read articles on moral decision-making, and notice that some of your favorite work is being done by Jesse Graham at the University of Southern California.
A 3-year bachelors probably doesn’t matter, at least I’ve not seen that mentioned in the admissions requirements at any schools I applied to. But some schools have course requirements, such as having a research methods or statistics course, a certain number of credits in psychology, etc. The GRE is usually required, and occasionally the GRE subject test is as well (although this is more common if you have a degree in a field other than psychology). You might need to take the TOEFL as well.
Judgement and decision-making are broad topics, so I don’t think you’ll have too much trouble finding good programs in desirable areas. One thing I might mention, is that if you’re interested in I/O psychology then you may want to consider business management (organizational behavior) programs as well. The funding tends to be better, and you do much of the same research; many business faculty actually have their PhDs in social or I/O psychology. The programs are sometimes shorter (4 or 5 years instead of 6+), and post-docs are not common; graduates are hired directly on as faculty members.
If you do get a PhD in social or I/O psychology, you could always make the transition into the business field later (like Jonathan Haidt did; he was a Social Psychology professor at the University of Virginia before joining the business faculty at NYU). But keep in mind, as @barrons mentioned, program reputation is more important than school reputation. For example, University A might have a top 10 business program, but their social psychology program might be ranked top 50, and they might not even have an I/O psychology program. But again, you need to look at research fit more than ranking.
A masters degree isn’t required for any of these programs. Since you’re not lacking in research experience and your grades seem good, I’d apply directly to PhD programs and see what happens.
As for what is realistic, that depends on your GPA and GRE scores (generally used to pass the first round of admissions decisions; they don’t mean much after that), your research experience and goals/fit (as outlined in your personal statement), and letters of recommendation, preferably from research-active professors in the field. I recommend applying widely, and not just to all “top” programs. You never know what the candidate pool looks like, whether they have funding to take on new students, or if your preferred advisor is taking students (its always good to apply to programs that have more than 1 faculty member doing work you’re interested in).