No, not all SACDs include a 2ch track. MOST do, but not all, which is odd.
SACD is a very nice format IMO, but you are coming to the highdef audio realm a bit late in the game, as both DVD-A and SACD have all but died out already. Titles will be tough to find and popular/better ones may be quite expensive at this point.
Oppo also offers the BD-80 which would give you Blu-ray capability in addition to SACD and DVD-A, so even though you don't intend to hook it up to a TV now, you would be able to in the future technically.
You could also look for a used Oppo 980H which was only $169 new and had pretty good SACD/DVD-A capability, and IMO, a much better investment into these formats. They should be selling for around $100-125.
If you are looking for a more heavy duty player, then perhaps a Denon 3910 or 3930. Even my 2900 is still an excellent player.