Honestly, just about any router will work, though you might want something with a higher reliability.

You just need to set a larger subnet size.  For instance the 10.0.0.0 net can route 16777216 IP's.

172.16.0.0 - 172.31.255.255 = 1048576
and 192.168.0.0-192.168.255.2255 = 65536

You just have to setup your subnet to the right size.