But what if I [need] to use a [symbol] from the nonstandard set? Am I screwed?

[Certainly] not!

Use these [HTML] 4 [Standard] codes [instead] of the symbols in the [nonstandard] set. (For the ones I don't have listed, I don't know what to [tell] you.)

€ -- € -- [Euro] currency symbol
, -- , -- elongated comma
ƒ -- ƒ -- middle-English lower-case S
„ -- „ -- double comma
… -- … -- broken underline
† -- † -- cross
‡ -- ‡ -- dagger
^ -- ^ -- caret
‰ -- ‰ -- [permille]
Š -- Š -- 20th letter of the [Slovenian alphabet]
< -- < -- alternative rendering for <
Œ -- Œ -- upper-case ligature of O and E
‘ -- ‘ -- right-facing quotation mark
’ -- ’ -- left-facing quotation mark
“ -- “ -- right-facing double quotation marks
” -- ” -- left-facing double quotation marks
• -- • -- alternate rendering of •
– -- – -- simple dash
— -- — -- alternate rendering for —
~ -- ~ -- simple [tilde]
™ -- ™ -- trademark symbol
š -- š -- lower-case rendering of the 20th letter of the [Slovenian alphabet]
> -- > -- alternative rendering for >
æ -- æ -- lower-case ligature of a and e
ÿ -- ÿ -- simple letter y with umlaut

HTML symbol reference