I'm just outside Oldmeldrum - feel free to get in contact after the school holidays if you are still looking. I usually hack once or twice a week, in the daytime
Also join Grampian Ponies' Lonely Hearts Club on FB, that exists for the precise purpose you're looking for. Not heavy traffic in that group, but a post usually gets a useful response within a few hours at most.
Also happy to travel, e.g. Bennachie, Kirkhill, railway line.