Words do not contain glyphs during annunciation. A man pronouncing a word is not a man pronouncing glyph 1, glyph 2, glyph 3 but sound 1, sound 2, sound 3.
So 300 is okay: I do not recoil from a foul glyph in it.
If you think so, don't you find "BRB" and "viz." OK too? My post's dad-post (though not by you) calls for avoiding such short forms on account of matching long forms' violations of lipographic norms.