2 inch four stud wheel (Seaham SR7)

These are about as common as hens teeth these days but I'm hoping someone somewhere can help me out. I'm told that an old Austin 1100 wheel is what I'm looking for to use as a spare for my trailer. It should be a four stud wheel with the hole center's measuring 4 and a half inches or 114 mm on the diagonal. Any help would be greatly appreciated and I can collect at your convenience. Many thanks.