Here are some of the amazing items traded through eBay.com. These are already sold, but search the keyword "paddlewheel" to see what's available now.
A penny bank once sold on the Mississippi Queen Steamboat gift shop in the 1980s.
eBay description: This is a Memory Lane ashtray much like the Currier and Ives pieces produced by Royal China in the 50s and 60s. This ashtray is the same shape and size, but has the pink acorn pattern around the edge and a Victorian paddlewheel water scene in the middle.
Steamboat logo on a pack of asparagus.
Steamboat logo on a cigar box.
Drawing of the Delta Queen.
Ad for a paddleboat in Floridaland.
Hard Rock Cafe steamboat pin.
Model boat kit.
Surrealistic steamboat music box.
Pencil sharpeners, including one of a steamboat (foreground).
eBay description: This Old English Staffordshire Ware decorative plate depicting the 220 foot Steamship Ticonderoga was made by Jonroth, Staffordshire, England for the Shelburne Museum in Vermont. It is 10 inches in diameter. The plate is in mint condition. There are no chips, cracks, or crazing.
A toy boat.
This isn't eBay, but may still be for sale at this URL: https://etsy.com