I think that a what i know as a math trade (from the board game community) could would be a good way to shift some stuff and get something useful in return. How it works is this
1. You post something you want to give away
2. You look through this list of things other people want to give away and choose what item or items you would accept in return for your item.
3. At a given date, all trades and wants are matched. you ship your stuff and await the arrival of the item you wanted
More info can be found here
https://boardgamegeek.com/wiki/page/Math_Trades