The Jellyhead choke will work just fine depending on the load you want to go with. If you are looking at commercially produced loads Environ Metal (Hevi Shot) pretty much has the corner on turkey load patterns. Personally, I would go with an Indian Creek .665, and Hevi-13 3" 2oz #6's. The Jellyhead should pattern well with that load also.
Either way before you begin patterning I would either deep clean the barrel or polish it. It really works.