I originally had yukkureimu say "suits me the best", but keine definitely uses the kanji for "similar" or "resemble". So I changed reimu's because her's can mean that too
>meh, the idea is preserved Except buying "The most similar one" makes little sence, and is pretty different from buing one that "suits me the best". I don't know moonspeak, but I figure the joke here is the miscommunication between Reimu and Mokou. Reimu wants to buy something that suits her, but Mokou understands she wants something similar- that's why she uses the "resemble" kanji.
I'd go with Reimu saying something like "One that would match my hair!", and Mokou presents a mask that matches her hair perfectly.