Help me target potential clients

I provide Wordpress website optimisation and I need to you to;

Find Wordpress websites from the UK
That are currently active websites
That have have some visitors so they are either start up business or medium size business
That have a performance rating of C or worse in Gtmetrix.com
Find the email contact or website owner

Then I need to email them from my email address with text I have template of offering services from me.

Please tell me how much per each lead?

Thanks