There are tons of "civilian" AKs. The Saiga is just one of many. Saigas are somewhat unique in being built from scratch as civilian weapons. Most AKs sold commercially in the US are former Combloc military weapons rebuilt around a new semiauto receiver. (Or, in the dark ages of the late 1980s around "demilled" receivers which are no longer legal, if they ever were.)
Confusingly, there is no standard designation for a semi-auto AK. You can find "AK-47" applied to both semi-auto and selective fire weapons.