Is this going to be used to study for a CCNA? If so, I'd suggest looking at Cisco 2500 series routers. You'll really need more than one router to practice routing configurations, I'd say three would be a good number. Firewalls aren't really on the CCNA, you'll just need to know what they are, but that's it. For a firewall I'd suggest buying an older computer for cheap, loading a Linux distro on it, and use iptables, or if you want something a bit simpler, look at IPCop. Dalight is the firewall.cx expert on it, so he can answer most any questions you have about it.
The administrator has disabled public write access.