The Ho-Chunk is Game On thus the GO logo. To the best of my knowledge, this is a company formed by a few ex Chipco employees. The mold is referred as "blank". They also have a mold that has 4 incursed GO logos on each side (see new Colorado Belle $1 chip). It is being referred to as the GO mold.
The Tortoise Rock is manufactured by Gemaco. Not sure if there has been a name given to the mold.