I, personally, would not call it a minor difference but they did similar with other of their double CDs (OG 3203 and OG 3209, for example) when they reissued them. I come back to the fact that both releases share identical barcodes, cat#s and tracklists and that, to quote the Guidelines, "Generally, there is a single page for each CD product/barcode. Please search for the barcode to ensure your CD is not already on 45worlds."
I can't see that the minor differences in the titles warrant a separate entry when the Cat#, Barcode and Tracklisting are exactly the same. Discogs would be the place for such niceties :-)
The two versions (this and the re-issue) have the same matrix numbers, should have the same title (I can't see any difference except for the word "rock" on the spine of the re-issue) and should be on this page together. The other entry is in my view superfluous and should be deleted.
@Quad5point1: Tracklist remains the same too, so I wouldn't think a separate entry is required. Perhaps Old Gold noticed their error (Mason Williams charted in Aug 1968) before they revamped the artwork which you added?