Need a way of allowing users to subscribe

Hey,

Need a way of allowing users to subscribe, I only need to gather emails wordpress side NOT send the emails that side.

Mailchimp etc are all no. It needs to be fully on my own site.
All mailing list services seem to be blocked on my VPS.
I have my own mailing list scripts I use via cPanel, but need a way of gathering the emails.

Not sure where to post this on here and the forums are literally painful to use here in navigation.

Thanks