Hi I've only just seen this. Have you found her? I hope you have!
My Siamese, Sly, stayed with my dad when I left home, because they were best mates & I didn't want my dad to be on his own. Then my dad decided to go on holiday, which was unheard of for him & off he went to the north pole
Sly came to stay with me. On the third day he sneaked out when my kitties went out. I looked everywhere for him, posted leaflets through doors & put posters in shops. I heard nothing at all, it felt like forever. I had put adverts in the paper, but I changed it to say there was a reward & got a phone call the day after!
A lady had seen him hanging about in her garden for a couple of days. As soon as I went into her garden & called his name, he came flying at me from the top of her garage, all purrs & kisses. The little monkey had been missing for nearly 3 weeks & only came home the day before my dad did. Where he was found, was about 4 miles from my house, he didn't know the area so wouldn't have known which way to go to come back. I think he was trying to get back to my dad's. Little lamb he had about another 15 miles to go.
Try offering a reward. Do more leaflets to hand out, asking people to check their garages & sheds, in case she's got locked in. Check any building sites, also any commercial units. Put up as big a poster as you can at all the large supermarkets in your area. Try contacting your council too as they usually keep a record of any cats that are involved in road accidents.
She's a beautiful cat, I hope you find her.