I threw together a userbox for anyone who wants to use it. The best explanation is this pointer to where I added it to my ENWP userpage:
https://en.wikipedia.org/w/index.php?title=User:Brianhe/Barnstars%2BUserBoxe...
It takes just one parameter, "membership" which could be member, supporter, board member, or whatever.
It's kind of tall because of the text below the logo. If we have a logo without the text, I can change it.