Laurie Jacobson, who is married to John Provost ("Timmy" from the "Lassie" TV series), runs Living Legends, which primarily books actors from TV shows that have been off the air for decades. The last I knew, she is (or was) the booking agent for Linda Blair. I don't have their address or phone number but perhaps you can Google them!
The Haunter's Depot
The Haunter's Depot -- You Can Scare Them! We Can Help! (A division of Haunted Ventures FX.) We are your premier source for Halloween merchandise. Thousands of products available including costumes, masks, static and animated props, changing portraits, makeup supplies, special visual and audio effect equipment, glow necklaces, lightsticks, and MUCH more!