https://mxroute.com/ https://mxroute.com/ 100$ lifetime, 360 outbound/hour. Or you could go with a yearly rate. Might want to read the terms of service for yo

https://mxroute.com/ https://mxroute.com/ 100$ lifetime, 360 outbound/hour. Or you could go with a yearly rate. Might want to read the terms of service for your usecase, but it works for me with low traffic and multiple boxes/accounts.