Reach out to Bobshirt or other collector groups on instagram, even someone like ChompOnKicks might be able to help out or even share a post for you telling people you're selling it.
eBay is the best option. Starting bid @ $150, put as much detail in the title as you can and go from there. Good luck Skatedad, and sorry for your loss.
What other decks are in the collection? There may be some that don't instantly look worthwhile but could be huge for a collector.