Indy is not enough for me, it must support SSL and be rock solid, can be commercial also
Indy 10's SMTP component supports SSL. What problems are you having with it?
Icsn (and Ics-ssl) components at : http://www.overbyte.be/frame_index.html
I've used IP*Works SMTP component before. I didn't do anything involved with them, I used them to send an email with error information basically. I have never used the SSL version either.
I don't believe you can purchase the components individually either.
I use Synapse library. It works very well with SSL/TLS. There is public wiki with information on "How To Use SMTP with TLS". It works with Delphi (I use Turbo that is based on 2006) and FPC. It is "normal" library, not component and in my opinion this is advantage for command line utilities or server applications.
SMTP is so trivial protocol (unless you use SASL or other exotic authentication methods) that any component would work. Of course, I would recommend our SecureBlackbox product. Freeware libraries such as Indy, ICS, Synapse to get SSL have bindings to OpenSSL DLL and also to SecureBlackbox (none of the listed has own SSL implementation).