Turn out to be a better shop

[gamboler]

This is the dialogue, taken from an American movie released in 1948:

Vincent: If Costello should turn out to be a better shop, you'll get out of all this Laurie.Laurie: Stop doing penance for me. Promise me that. Nobody can help me anymore.

Context: Vincent is Laurie's brother. Laurie is married to Durant, a dangerous gangster. Vincent is an alcoholic doctor who wants to help Laurie. Costello is one of the gunmen of Durant, a second-in-command.

Being that "shop" as a noun has a lot of different meanings (atelier, workshop of an artisan, small retail store, any factory, office, business, etc.) but none of them make sense in the context, my question is:

What does shop mean here? Could it be "shopped" or "shot" instead of shot?

 

[Matthew Wai]

I think it should be 'shot', as Costello is a gunman.

 

[gamboler]

Thanks Mattew Wai. If the word is "shot" as you said, what does the sentence mean?
Shot like "shooter"? Or maybe shot as "being shot"? The second one makes more sense in the context (if Costello died, Laurie would get rid of her problems), but I don't know if you can express the idea this way. If that's the case I'd say "Turns out to be shot" Why does he put "a better" before?

 

[Matthew Wai]

See definition #2 at http://www.oxfordlearnersdictionaries.com/definition/american_english/shot_1?q=shot