Moss Motors has the hubcap centers. They are $8.50 each.
See http://www.mossmotors.com/Shop/SearchResults.aspx?SearchText =hub%20cap&WebCatalogID=9
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster
If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)