Do you know mailerking?

Where can I buy it?

I mailed them to buy it, but they didn't asnwer yet.

Is there any other option like mailerking?

I'm finding email sender using gmail, yahoo.com like those.

Any suggestion?

Damn, throwback, I used to use MK to mail idiots who posted their naked email addresses on CL... good times.

Not sure about similar options, but I'd imagine you get a reply if it's still functional. Looks like they added a new bot for sale on 3/30/16.