Looking for Advice on a Video Card or Converter

Hello,

I have a Mac Pro and a Rear Projection HD TV almost ten years old with only Component in for an HD signal (no hdmi in). I have a nice Apple 30", this is my primary monitor, but even tho my tv is ancient, it still has a good picture & looks great in HD, so I'd really like to use it for movies.

I've read lots of reviews on converters, mostly saying they're awful and not to bother.
My goal, obviously, is to get the best signal possible, I'd really love to get 1080p if I can. If I can't, I'd probably rather go 780p because 1080i looks awful, this tv doesn't handle interlacing nicely at all.

I'm open to either a converter (DVI to Component Out), or a card for my Mac, whatever will do the trick!

So far, the best I've found in my research is Black Magic's DeckLink Studio, which is $695.
I can't tell for certain whether it does 1080p for component out, and not just 1080i.

My current video card:
NVIDIA Quadro FX 5600 (1536 MB vram)

Hoping for some suggestions or thoughts, thanks!
-Adam