I have two front seat belt buckles. I'll say $25+shipping to get a number out there, but definitely make me an offer!
I have an alarm system from when I was obsessed with VW-style flip keys. The keys come with little Mitsubishi logos and key blanks that are compatible with our cars. Never installed. Asking $40+shipping.
I have a keyless remote entry system which comes with Audi-style flip keys. This was installed in my car, and recently removed. The rubber coating on one of keyfobs has become sticky with age. The other is unused. Keyblanks are also included. Asking $20+shipping.