Tiermann,
Many thanks for the parts suggestions - the top and the holder were what I had in mind. Forgot about the bowl with the socket in the middle - that will work!
As for painting - which paint would be best (washable so I can return to their original conditions in the future if need be - most likely will leave it alone for future builds.).
Adding those to my ever-growing list of parts to order
(Finally went through my collection of 10 Rubbermaid tubs and inventoried the broken bits and lost bits that need replacing - thankfully a short list!)
Will be sure to post pics once it is done and up.