Besides the expensive and hard-to-find Morette aftermarket tail lights for 04-07 models, I don't think any exist. You're pretty much going to be limited to stock 04-05 red tail lights, 06 grey tail lights, or 07 chrome tail lights. As you already know, you can customize them by completely or partially tinting them with red or black vinyl or paint. Some people have resorted to cutting the housings apart and painting or altering the insides, sometimes to include LEDs. The problem is that if you're not a perfectionist and you rush the job, they'll look crappy and you might get moisture inside the housings.
07 WRX (Albins 5MT + Blouch 20G)
Jorge Carrillo Tuned (365 whp/340 wtq)