Huh.
has the tilde-like thing slightly offcenter.
Try U+0303 Combining Tilde.
What's the Unicode of the circle with dot you used?
Arial doesn't have it. Do you know what fonts do have it?
Edit: Nevermind:
⨀ ⨀
So:
⨀̃
⨀̃
̃⨀
̃⨀
Might as well have it moved to "Typesetting dashes and related glyphs".
Please and thank you!