How about just paying people for their organs? Let the market work. Is that really such a bad idea?
Poor people are the most likely to be exploited and the most likely to use their donated organs. It's been shown that empirically economically incentivising organ donation crowds out altruistic organ donation, a non negligible source of supply and that those who donate for money do not experience a long term economic benefit but do experience long term health consequences.
You also create an unnecessary class problem as middle and upper class people have access to organs, but not poor people who are the actual source of supply...