Just my thoughts on the artwork, I don't think it's a forgery or a fake. It's pretty nice, but the value is as a sports collectible. I have no idea what it may sell for in a sports auction.
Maybe not an exact comp and non-sports, but here is a portrait of John Rennie the Younger, who took his Dad's plans and built the London Bridge.
www.liveauctioneers.com/item/131508185