While visiting the Portland, ME Boat Builder's Show, I visited the Portland Hamilton Marine Discount store and found covers to replace my 1987 vintage 5.0 circular Data Marine instrument covers. If anyone needs the older instruments, the Hamilton part number is DAT-FAB-1305L 302B 20H.
Joe
Thanks for the input.
Also try this:
http://www.c34.org/phpbb/viewtopic.php?t=1313&highlight=wintron
Joe,
They are also routinely available on eBay (from DMI Marine) for about $1 each. Do a search for "Datamarine" and they usually come up. I think DMI sells them at cost, using these covers for cheap advertising on eBay.