whoops -- meant digital to RCA in the topic title

I'm sitting here listening to the music in Norfair in Super Metroid buzz the hell out of my TV's speakers and it reminded me that I need a good audio solution for my set up.

I have a panasonic plasma that only does optical out for external speakers, so I can't connect my Swans M-10s to it. I love these speakers, so I'm having a hard time replacing them, since I know I won't get anything on par for the price I paid (about $80, iirc.)

I was thinking of getting this:
http://www.amazon.com/Digital-Audio-...cmu_pg__header

but yeah, that's another $57 I'd rather not spend.

is my only other option new speakers?