I think the closest analogy you can make with the story of the Good Samaritan and Scout would be to connect the way the Good Samaritan helps the Jew he finds along the road and the way that Scout helps Boo Radley. There are similarities and differences between the two stories obviously but I suppose the analogy is relatively sound, particularly in terms of what it says about their characters.
The Jew has been beaten and left by the side of the road without money and gravely injured. Boo has also likely been beaten but is hidden away in his house; the injuries or the problems are not obvious. But just as the Samaritan takes it upon himself to do whatever he can for the Jew, Scout tries to understand what it is about Boo that keeps him hidden away from the world. Boo also has the ability to reach out to Scout and does so by leaving her and Jem gifts and watching out for her so there is more reciprocity than in the story of the Good Samaritan where he does what he does without thanks.
There's also not quite as clear a resolution to the story in To Kill A Mockingbird since Boo rescues Scout from her attacker, whereas in the parable of the Good Samaritan he saves the Jew and then makes sure that he will be taken care of and goes on his way; the two do not interact again.