Write To Them plugin to find MPs / Campaign tools

Hi –

I’m setting up a Campaign site which needs to allow it’s users to Take Action by sending Email letters to their MPs

There are a couple of plugins which allow Email letters to be sent to pre-set email addresses, such as:

http://www.louder.org.uk/plugins_wp.php
http://speakup.designkode.com/demo

But these don’t seem to let the user choose / find their MP to be able to target them specifically. There is a service for this called: Write To Them:
http://www.writetothem.com/

eg – so my local MP would be:
http://www.writetothem.com/write?who=46923&pc=E8+4NS

They DO provide this WP plugin:
http://www.writetothem.com/about-linktous#plugins

but it’s not listed on the WP.org site etc. Does anyone have any ideas / experience of this please?

Cheers
.ben.