Hello,
There is also an SRF235.
http://www.robot-electronics.co.uk/s...angers1999.htm
http://www.robot-electronics.co.uk/htm/srf235tech.htm

Another ultrasonic ranger is the PING)))
http://www.sander-electronic.de/gm00035.html

A few things to maybe add to your list.
Greetings,