My inlaws are a buying a house near us that was built in the 80's.It is around 2000 sq feet including the basement.The previous owner had a freestanding wood stove in the basement.The walls are concrete along with the floor and he had it sitting on a brick pad.My question is,it appears the old stove just had the black stovepipe that ran thru the cement wall,it has a round clay liner that is 6 3/4 inches in diameter.The clay line runs straight into the flue.There is no stainless liner.Will an englander or any woodstove work like this?It appears the flue may be 8 0r 9 inches in diameter.Also which englander would be best,the 13 or 30?Thanks for any help,as they are tight on money,but I want to make sure everything is right and safe...All the clearances are good.