Not surprising, as this is often a proprietary part. If you had the serial number of the part, you might be able to get a good electronics to cross-reference it for you, but in the end it could well be a wild goose chase. Why not an Apple dealer? They should have them. You don't want to replace this on your own anyway -- lots of high voltage. Ouch!
I remember -- you were the one with the flickering video and I suggested that it was probably a failing flyback transformer. Were you ever able to verify this as the problem?