Wow! I am surprised at how many people hav found specific horses on Kijiji. You can count me in on that lot as well.
Sam is my old man Clyde x. We got him as a 3 year old, over 17 years ago. About 8 years ago, we reluctantly sold him to friends who we knew would give him a great home. At the time, my kids were quite young making iit difficult for us to give him the time and attention he deserved. A couple years later, we learned he had been sold again. I was disappointed and prayed he had a good home, especially since I knew he was getting on in age. I wasn't really looking for Sam, but worried about him. In June of 2011, I stumbled upon an ad on Kijiji from another part of the province. He was for sale again. By that time, my kids had become much more independent, my daughter was an avid rider and we had just moved to an acreage where we had the space for more horses. Needless to say, it took all of 5 minutes to decide to buy him back.
Now, he is 21 years old and happily munching in the pasture with his "herd" just outside my kitchen window. Between my daughter and I, we ride him at least twice a week, saving our weekend trail rides just for him. My husband thinks he has won the horse lottery. I don't know about that, but I do know he has won my heart all over again and I may have also won his.
I guess the point of telling you this story is to say don't give up. It is possible you might not find your horse, but when you least expect it, you might. If / when you do, the horse will remember and it will be worth it.
I sincerely wish you the very best of luck in finding your horse again.