Starting an opt-in email marketing campaign but isp only allows 1000 emails per day, what do i do?

I WOULD LIKE TO KEEP THIS ISP BUT ALSO WOULD LIKE THE ABILITY TO SEND AND RECEIVE UNLIMITED EMAILS.
Starting an opt-in email marketing campaign but isp only allows 1000 emails per day, what do i do?
Check for a upgrade and if you send me a SPAM I might send you B.S. credit card information so you waste you time and money.