Best bet is to contact a wood burning stove dealer and buy the chimney liner kit to fit your house. Then install it with the help of a friend. National Fire Protection Association standard is to run the liner all the way to the chimney cap. It does matter. An insulated liner all the way up means improved draft all the way to the top of the chimney. This means a MUCH more efficient stove. Running the liner just to the damper means you won't have a great draw all the way up the chimney, still a chance of chimney fire, and in a year or two, you'll pull the whole thing out and redo it the right way anyway.