Need help choosing sound sensor

Ima Noob here. I finished working through the arduino starter kit and have been looking for other projects. I got the book Environmental Monitoring with Arduino from Oreilly Maker Press.

In it there is a project which calls for this sound sensor. Apparently the board amplifies the signal from the mic to a point where it is readable by the Arduino.

I'm not in the States, so the above sound sensor, with duties, taxes, and exchange rate will end up being too expensive.

I've found these alternatives on amazon:

Man Friday
C. J.
BBS
uxcell

Can anyone help me figure out if one of these might be a suitable replacement?

Thanks in advance.

They are all the same; an electret mic and a comparator...
like this one: http://www.ebay.com/itm/Microphone-Sensor-High-Sensitivity-Sound-Detection-Module-For-Arduino-New-/262186318629?hash=item3d0b85bb25:g:6sUAAOSwbdpWamuj

The sensor signals when the sound lever reaches a preset level. (digital output)

Thanks for the answer!