PRU of AM1808

I am using the PRU of AM1808，Used to generate Suart.
In the package from TI, It use the serializers and transmit or receive data pins of the McASP.
My questions is:

1. If i can use other PRU's pins to transmit and receive data,not use the pins of McASP?
2. For generate Suart, the serializers must?
3. If i use the two PRU modules, both generate Suart, How many can produce?

My product needs 10 serial ports, Except 3 Huart, but also needs 7 Suarts from the PRU.