OK .... so ...
We have two frequencies going on here, and some confusion as to the requirements of the "baud" rate.
The interface speed of the GPS is the baud rate, the rate at which it sends messages is the message rate, the two are not really inter dependent unless you are expecting to be transmitting data at 32 baud
So even if the messages are coming in at 10Hz unless there is a VERY good reason why not then they can also go out at 10 Hz independently of the baud rates.
The very simple serial repeater posted by Rob will do what you want, all you have to do is extend it to have the number of ports you are expecting to repeat to and specify the pins you are intending to use for the soft serial library. Most NMEA sentences are quite short and will not require buffering but can just be squirted directly out.
If you need more guidance with the coding just shout, I am sure there are plenty of people including myself who can knock this up in 5 minutes for you.
If my understanding is too simplistic and you do need to be throttling the NEMA message rate then it all gets much more complicated.