You're on the right track. 研究会 is commonly used as the name of a culture (文化系) club at high school, and no one thinks 漫画研究会 (or 漫研 for short) refers to a serious academic society. Usually "Comic Book Club" should be enough.
However, there's one catch; depending on the school, the name 研究会 (or 同好会, 愛好会, etc) may be used to refer to a smaller group which is not large enough to qualify as a "proper 部" with a financial support from the school. For example, please read chiebukuro questions like this and this. You said this 漫画研究会 is one of the (proper) culture clubs, so this distinction may not be important in your story. If the difference is important, perhaps "circle" is a good candidate as the translation of 研究会 (see this for example).
僕の学校では
研究会⇒同好会⇒部活動 と昇格する形です
研究会は出来たばかりの団体です。
実際の違いは部費が出るかどうかです。
(typo corrected by me)