You can get these round (and some square) pinback buttons in a range of sizes, from a self-effacing 1 1/4" to an emphatic 6".
The prices shown are for the 2 1/4" size.
Now, granted: you might rather have a penannular brooch. But unless you're gathering your cloak around you these may be a bit more practical.
They won't leave those huge holes in your clothes, for one.
Of course if you really do want a penannular brooch on your shirt - while avoiding the gaping holes problem - you might try this.
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