Unfortunately, I don’t know any online website. I had to reach out to my friends in Korea. Alternatively, what you can do is you can contact alminwon.com and there are many other agencies who issue that doc but they charge around 500$. It’s expensive but gives you a sure shot. I was planning to opt for that but during my time of application the laws were stricter and they were not issuing this doc. But I have heard and saw many people getting it through them now easily.
Thanks for the info. I will look into it. Just sent an email to embassy hoping to get any result. The site you sent above (alminwon.com) seems to be down though. Thanks again!