87GN, In addition to the parts Dusty53 mentioned above, I think you said you were looking for front wheel hub bearing grease dust caps??? If so, a bit of Chevy Master Parts book searching shows the original part was listed in 1929-57 book as GM# 3680897 - Cap, wheel hub, grease 2-5/16" OD that fits 1946-57 3/4 & 1 Ton trucks. A latter book indicates that was superseded by GM# 3768604 and that lists as fitting 1946-62 3/4 & 1 Tons as well as 1963-66 C-20/30 series trucks. I couldn't find anything offered on the web for either of these GM part numbers.
However, a search for 2-5/16" OD grease hub caps came up with this
Dexter 2-5/16 OD pair of hub capsthat may fit your need. There were a bunch of other similar diameter caps, but none that seemed to have the possibly needed cap height for your truck. Hope this may be of some help.
