You can fit the original style hubcaps to rally wheels here's a picture. http://i103.piczo.com/view/3/h/b/5/2/u/p/w/0/w/z/t/img/i297948060_40856_5.jpg

there's some more detail on this page,
http://millpower-race-engineering.piczo.com/?g=45768718&cr=5
you need to scroll down for the section on hubcaps.

stuart

1950 Chevrolet 3100 (occasionally working) truck:https://c2.staticflickr.com/6/5490/30684982201_6dc479d18d_c.jpg
1928 Chevrolet AB National Phaeton: https://c4.staticflickr.com/6/5573/30137792083_42886d30a4_c.jpg
1932 Austin Special Sports: https://c8.staticflickr.com/6/5793/30116567183_1520e67c4d_z.jpg