They will be steels from a van or people carrier running 5x120 pcd hubs. Quite cheap if you know where to look, typically £30 to £40 each, but watch out for the high ET on most - an ET of 20 or less gives the dished look that goes well with classic cars, anything higher and they start to look like, well, van wheels.
http://www.oponeo.co.uk/steel-wheels