SES Temporary Burst Limits for Initial Service Launch

We intend to use Simple Email Service for sending account activation emails for a globally available service. The standard limit of 14 sends / second should be plenty for regular usage - but we expect there to be a large influx if new users when we first open the system and are concerned the SES limits will be a bottleneck. What's the best way to ensure SES can handle this initial spike in registrations? Are there burst limits available? Do we simply need to ask for a larger quota? Or will we have no choice but to perform rate limiting for our initial launch? Thanks!