That's really great work and $10-$25 is far too little for that kind of quality. People who appreciate work like that will go $50 plus for somebody they collect. Also I agree with others on the 1/1. Get it machined on there or maybe a sticker on the back.
Thanos Super Collector.
Always buying Iron Man 55, Captain Marvel 33, Avengers Annual #7, Various other Bronze Age Thanos appearances.