I now have snap in wheel covers on our Mountaineer,two of the plastic factory center cap covers flew off while traveling and were too expensive to replace IMO.Snap in covers were a quick & easy fix.
I bought the new covers at Walmart... 16" wheel size and they look ok,a spoke mag wheel design.The covers have been on for over five years and fit nice and tight,used my hand to knock them in the wheel lip.The price was around $18.00 for a set of four.
On our previous TT I repainted the white spoke wheels due to severe rust from many nights of ocean front camping.Looking back it would have been quicker and looked better with snap in covers.