The largest I have done are Butts. I had cured them to make ham, bagged and SV then, smoked and finished in a 500° oven.
I have 2 machines. A Vacmaster VP 215, which would probably easily do a chicken not sure a turkey. The suction sealer is a Pro380, it will do a 15" bag, that is what I used for the butts.
Not sure on the SV whole chicken, as the water would no be in contact with the inside, maybe if it was spatched or done in halves.
probably more knowledgeable folks on here when it come to the SV chicken thing.
Good luck, hope to see it when you do it.