Escuan, I do not have access to OED but the online American Heritage dictionary (www.ahdictionary.com) has two pronunciations of the word. The first rhymes with 'bean' the second rhymes with 'fine'. Neither rhymes with 'bin'. So I think it's ok.
I do not agree that the five unclued entries form a series. They are closely related to five c*******s that form a series but they, themselves, do not.