Help with '77 Century Station Wagon hubcaps

We a '77 Buick Century Station Wagon. When we purchased it, it had the spoked hubcaps with the Buick emblem in the center. Someone jerryrigged the emblems with silicone or something and now they are all falling off. Does anyone have instructions on how these are supposed to attach? It looks like the emblems have clips on the back of them, but there is nothing for them to attach to. I would appreciate any assistance!

Here are some photos of what I am talking about, note that two of the emblems have different type of fasteners on the back :

I believe those might be after market "wire wheel" covers with Buick centers glued on

Ebay will have replacement centers or you could pic up an entire set of wheel covers with the correct center pretty reasonable for these years.

Edited April 8, 2014 by my3buicks (see edit history)

A google search showed Keith has it right.

However I think the picture above shows the hubcaps have many more spokes than the pictures of the original poster.

While the stock pan hubcaps are somewhat bland in my opinion

You can easily upgrade to a set of the Buick Rallye wheels which can be found in both 14 and 15" versions.

Thanks everyone for the responses! Looks like I will need to consider my options, although I do want to stay original.