Is 卜 a frequent variant of 下? 卟(ヤ) seems to appear frequently in the Japanese-Chinese music book 月琴楽譜, which makes more sense if 卟 were a form of 吓. 虲=蝦 seems to be known, appearing in 汉语大字典. Would it be reasonable to normalize ⿰口虲 to ⿰口虾?

Personally I don't agree with the normalization suggested in comment #14033, because

1) 虲 and 虾 are too different as both 卜 and 下 are frequently used characters and we have to look up the dictionary to learn the relationship between 虲 and 虾.

2) Usage of 虲 long predates usage of 虾. The former is attested in 《正統道藏》 (v.164 line 2 character 3) published almost 600 years ago, while the latter is a PRC simplified form of U+8766 蝦 established in the last century. Because the original evidence is published before 虾 was created, the text produces the current form ⿰口虲.

3) Both 蝦 and 虾 are not very productive:

which means if we indeed normalize ⿰口虲 to ⿰口虾, we can potentially only save a few code points.