Minecraft maximum number of villagers in a village?

Is there a maximum number of villages in a self-built village?

Yes, the number is determined by the spatial characteristics of the village, i.e. How many conditions are met and how often that an offspring is possible.

Depends on whether you mean how many you spawn or whether they spawn themselves

Well - the answer to both is theoretically "yes".

Apart from the technical limitation, there's no limit.