You won't find much genitalia wise for Aiko 3 due to the fact that the original Aiko 3 was seen as a child like character (Although there were morphs to make her appear older, as far as most of the stores were concerned Aiko and Hiro were considered non adult so vendors were limited in what could be sold as far as add ons.)
Also keep in mind that most of the gens if they were made in Aiko 3's era were either morph assets, used Geometry switching (which worked in Poser and not so well in Daz Studio), a parented prop, or a conforming figure (Which did not always work well, and some left a slight but visible gap between the gens and base figure, I'm also thinking that this method was largely introduced with the 4th Gen figures, mainly M4, as Daz's solution for the females was still making a crease morph in the gens area, though there were some 3rd party options for V4.)
Geo-grafting did not come along till Genesis and I'm not sure if geo-grafting will even work with figures earlier than Genesis.
So short of a few morph options, maybe some prop figures, and the Magic Perfect G there were not many options for Aiko 3, and Aiko 4 only fared a bit better because her generation was built on the major characters being morphs and maps for Victoria 4 base. (Which was largely carried on with the Genesis lines, however even when Genesis was introduced and the anatomical elements were available only with the pro bundle purchases, Aiko's bundles have largely been excluded from containing the Anatomical Elements, though if I recall correctly Aiko 7 and Aiko 8 did have gens maps)