Rusty old unused pram or similar (Dunblane FK15)

Hi all. I'm needing something like an old pram or something that has pneumatic wheels on it. I'm revamping the trolley I use to chauffeur the cats to the vet because the wheels just don't absorb any of the bumps along the way in the pavement and it can't be very comfortable for them. If you can throw up a pic that would lovely - I'll look at anything! Many thanks!