<<So I have 2 alternatives:
Get a solid door and try to make it decorative somehow...OR
Build my own door.
Building your own door isn't that hard. The challenge for you if you
don't do this kind of work will be trying to fit the finished product
into the old frame. You will build your door square (all right angles)
and then have to trim it to a frame that is no doubt out of square and
out of plumb. Probably out of level, too.
If you build your door, I would strongly suggest that you take the time
to find some honest to Pete kiln dried wood. Buy the lumber yard crap
that looks good will give you green wood that is sawn in such a way
(mostly flat) that will guarantee twisting and warping.
I think Martin is on to something with the salvage yard if you can find
something nice at a reasonable cost. However, the salvage yard by me
gets more for a door than I think I should pay since every one he has
needs scraping, sanding, painting, and has already been trimmed,