However, if you are not planning to have more than 1000 recipients, t2.small will do as well.
Make sure you have a security group associated with the instance that allows inbound SSH, HTTP, HTTPS & SMTP.
Note: If you are connecting from a windows host you need to convert the PEM file first. You could use PuTTY with a private key to connect to your Amazon EC2 Linux instance. To do so go through the following steps described in this guide: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/putty.html
In case you are planning to purchase LUCY or you are already a commercial client you can contact support@lucysecurity.com to open a ticket. We will get in touch with you within 24 hours.
In EC2 environments we have clients reporting that there is a limitation in the amount of outbound SMTP traffic. The limit is 200 mails a day and 1 email per second.
More details here: http://docs.aws.amazon.com/ses/latest/DeveloperGuide/limits.html
Also, AWS does not support phishing simulations through SES as this is risky for Amazon public IP to get blacklisted. To avoid the limit and send not more than 200 mails per day, please use the Scheduler which helps to distribute the sending messages over a longer period of time.