Looking for home for 6 month old cat

We've been calling her Holly, she showed up in our backyard a few weeks back during Christmas-time and never left. We've put up missing cat posts, we've had her checked for a chip but she has none, no signs of any ear clips or fix-markings. She's an indoor-outdoor cat, she lived fine outside (even caught a mouse for us), but she wants to be inside in the warmth. We had her checked for FLV, Rabies, etc and she came back negative on everything. Personality wise extremely people friendly. She's a lover, wants to snuggle, wants to be pet and held. We have other cats and while it's always been through a glass door she's never hissed at any of them. She is a bit timid, she's always getting her food stolen by a neighborhood calico and she runs and hides rather than fights. Vet says she about 6 months old, weighs 5.5 pounds, and she's not going to get much bigger. She does have ear-mites which we are treating with meds from the vet but those will be gone soon. Otherwise she's in good health. We'd keep her but already have 3 and just can't handle any more. I've reached out to Bradshaw animal shelter to see if they can take her in but we've received nothing back from them, so now we're looking for homes ourselves.