Modifier: :currency

Choice price, formatted as money. Write it after a colon: {Toppings:4:currency}

About

Same value as price, run through the entry currency formatter.

Product	Gravity Forms
Requires	Gravity Forms 1.9 or later
Works on	Checkboxes, Radio buttons, Drop down, Image choice, Multiple choice fields
In the picker	What to show

Where the merge tag picker offers it

Form fields: Drop down · Radio buttons · Checkboxes · Checkboxes, one choice · Image choice · Multiple choice.