Would it be possible to use the pic's hardware USART set at 9600,8,N,1 and receive and transmit data to the 7,N,1 device by simply massaging the bits some.

When I receive the bytes, I would shift them to the left once and store just the 7 bit value as a byte.

Before sending the bytes from the array, then make sure the 8th bit is a 1. Wouldn't the 7,N,1 system see this as 7 data bits and two stop bits?