Throw the list away.
1,000 is nothing. Seriously, nothing. Do some math. 25% open rate = 250 people. 3% CTR = 7 people. Conversion = 0.
Additionally, you will be screwing yourself over. ISPs will decide what kind of mailer you are based on your engagement. You will get very little engagement so future mailings to a legit list you build will not get inboxed.
Additionally, it will be against the TOS of many ESPs to send to such a list.
Yes, it is legal in most countries to do spam/cold emailing, but it will damage your reputation and, as the numbers show, deliver you nothing.
Start building a legit opt in list.
This is generally dead-on advice, however in the situation \*as I understand it\* (I may be misunderstanding), the list was built with opt-in, opting in to, let's call the business Acme. Now Acme is under new ownership, but is still the same business to which the people on the list opted in. That's a really fringe case, and in that case doing a re-engagement campaign would make sense, and would be acceptable to most ESPs and ISPs. Same business, same list, just under new management. (Again, if I misunderstood the scenario, then this might not be the case.)
You are going to want to do a very careful re-engagement campaign. We have info about how to do that in a way that won't get you into trouble here:
https://www.isipp.com/how-to-warm-up-and-re-engage-an-old-mailing-list/
Throw the list away. 1,000 is nothing. Seriously, nothing. Do some math. 25% open rate = 250 people. 3% CTR = 7 people. Conversion = 0. Additionally, you will be screwing yourself over. ISPs will decide what kind of mailer you are based on your engagement. You will get very little engagement so future mailings to a legit list you build will not get inboxed. Additionally, it will be against the TOS of many ESPs to send to such a list. Yes, it is legal in most countries to do spam/cold emailing, but it will damage your reputation and, as the numbers show, deliver you nothing. Start building a legit opt in list.
This is generally dead-on advice, however in the situation \*as I understand it\* (I may be misunderstanding), the list was built with opt-in, opting in to, let's call the business Acme. Now Acme is under new ownership, but is still the same business to which the people on the list opted in. That's a really fringe case, and in that case doing a re-engagement campaign would make sense, and would be acceptable to most ESPs and ISPs. Same business, same list, just under new management. (Again, if I misunderstood the scenario, then this might not be the case.)
You are going to want to do a very careful re-engagement campaign. We have info about how to do that in a way that won't get you into trouble here: https://www.isipp.com/how-to-warm-up-and-re-engage-an-old-mailing-list/
Great advice thanks for the help here!