Inara's Red Beaded dress appears in Shindig.
More after the break:
The above was a promo picture.
Some screencaps from Shindig:
If I remember correctly, this dress was from Shawna's stash and it was auctioned off a few years ago.
Costumer's Guide has more information here.
My Photobucket Album for Inara.
Serenifly Costumes site for Inara.