I have a pair of Klipsch Heresy HBR speakers that I bought new in 1980. Only used occasionally and still in great shape. Is it possible and/or advisable to use them as part of a home theatre system to save some money versus buying new ones? If so, in what positions (which speakers in the system) should they be used in the room? Also, what additional speakers should I buy to go with them to complete the system keeping in mind I am trying not to sink a lot of money into this (no more than $400 to