I did a show WAY back in the late 80's with one of the first ever infomercial type deals, first shopping channel ever, in fact. It was for the Cajun Injector, which was pretty regional back then, but now can be found in almost any large grocery store. Usually they have a mason jar of juice with an injector shrink-wrapped to the bottle. Syringe is pretty durable and lasts forever, but juice can be bought in bottles again or can be your own experiment. Some combination of brine, broth, spices, worchestishire sauce, hot sauce, etc. Look in the section with the BBQ sauce, worsh, etc. The needle is specially designed, with 3-4 exit holes around the needle. In fact, the point has no hole, it is semi-pointed and solid. The juice comes out the sides of the needle.
http://www.cajuninjector.com/
but like I said, you can step out to a large grocery store and find em. In fact, they should be on special display now that it IS thanksgiving.