You're right, it used to be the norm in Korea.
In most of the Anmabangs discussed here that cater to (or at least tolerate) foreigners, you wouldn't find it today (and probably not a great idea, safety-wise). You could probably still negotiate for it with some of the ladies in Itaewon Hooker Hill or the other RLDs, but given the volumes that they do I wouldn't recommend it (particularly on Hooker Hill, which primarily caters to foreigners). If you've got time and are feeling more adventurous, you could try the RLD in Suwon.
Your best bet for this kind of paid action is the private brothels or officetel services; in my experience, in many of them you have to ask them for a condom, as they won't automatically provide it (there's no way to determine this ahead of time, however, as asking questions like this via sms will get you shut down). The only problem with these however, is that you need to speak Korean, and even if you do, at least 80% of the time they won't take a foreigner.
Of course, the other option is a civilian pickup. Again, in my experience, most Korean women won't automatically go for condoms. That being said, if you surprise them with CIP, you may get a very negative reaction: while being lax with condoms, many (most?) young Korean women also don't take birth control. Go figure.
Some cultural context is key here: Koreans view themselves, even today, as being a "pure" race, free from major disease or defect. Incidences of STDs are at the low end of the range (despite the sexual culture) and in particular the incidence of HIV is very low. This is coupled with very poor sex / health education and a Korean male (or, let's face it, all male) preference for BBFS, which, being a male-dominated society, many women acquiesce to even if it's not their preference.
I must say I have many fond memories of pumping my load deep in beautiful young Korean girls' hairy pussies (and never encountered a single health problem).
