I agree - that looks like the timebase for the real-time clock. Should be pretty easy to find a replacement, the Sparkfun crystal that 360alaska linked should work, or get it at DigiKey along with your other replacement parts.
Elfen, how did you know D1 and D2 are diodes? Just from prior experience troubleshooting SE/30's? I guess since their names begin with D, that's a good clue too.
If that is a SOT-23 sized footprint, then these diodes may work as replacements: http://www.digikey.com/product-detail/en/BAS16-TP/BAS16TPMSCT-ND/717314I would be nervous about traces that have been eaten through with defects that are too small to see, or are even inside a via or inside one of the inner board layers. It would stink to replace all the components and have the board still not work.