In article ,
says...
Second response since I've looked into replacing these parts. I can get
a replacement flyback transformer supposedly for $81.70 at PartseStore.com

http://www.partstore.com/ModelDetail...delID=168 744

It fits my television model perfectly, but I don't know if that's T900.
There's one for $74 also; what do I use?

4835 140 67104 is the original part number, and
4835 140 67128 is the replacement number.
Either one would work, but you will probably find that 67104 isn't
available unless someone has one that's been gathering dust on the
shelf for quite awhile.

Q906 is a D1556, with "4E" printed on it in smaller letters. Discarding
the 4E, I can get a replacement NTE2331 for ~$6.

Should work. 4E is probably a date or batch code.

I see the transistor is used for horizontal deflection. So would that
explain the lack of display right there? What about vertical?

No, actually Q802/T801 does horizontal deflection, tube filaments,
28 Volt supply for vertical and a couple others. Q906/T900 does
only the High Voltage for the CRT's, which is (usually) why you get
no picture but everything else works.

Given that fuseable resistor and that transistor are burnt, what else
should I consider replacing?

Usually T900, Q906, R934 are all that is needed, unless there is
something else wrong with the set. I'd give the solder joints a good
visual inspection while the board is out and re-do any that look bad.
Barring elctrical problems, it's likely to need fluid change/optical
cleaning, minor convergence and color balance tweaking.