Looking for a Home for "Roxy" - URGENT (Strawberry Mansion, Philadelphia)

My partner Matt and I have been rehabilitating this sweet girl for the past year. Roxy is a ~3 year old brindle pitbull mix, spayed and with current shots. We found her abandoned in Fairmount park after recently giving birth & nursing with no sign of her puppies around. She had scarring on her neck, damage to her ear tips, and was very timid around people standing near her, but she immediately bonded with our other two pitbull rescues and now lives with them alongside our two rescue cats. Sadly, she has an attack instinct with small animals. She has killed two stray cats that got into the yard. A month ago she and one of our other dogs collided chasing after the same ball and got into a fight requiring an emergency vet visit and wound care. Last week, Roxy attacked the same dog again when they tried to take a toy from her. Before this, there were no other incidents between any of the dogs. It seems possible that she was previously trained to fight or hunt, but she has a huge, kind heart. She loves to snuggle on the couch, play with the garden hose, and leap around. She can run alongside a bicycle as fast as you can pedal. She also has natural herding skills. She would do really well in a single-pet household or maybe as a companion on a farm, as long as she is with someone who can give her the attention and specialized training that she needs. With the safety of our other pets in mind we can no longer keep Roxy. We recognize surrendering her to a shelter would mean she would most likely be put down. So we really want to find a good home/foster/rescue for Roxy this week. Otherwise we will put her down so at least she can be surrounded by people and animals that she loved instead of it happening alone after a few days in an overcrowded shelter. Please contact me as soon as possible with any interest or leads/suggestions to help Roxy find her forever home.