I haven't messed with it but you may be able to use a non-linethrough font in say black for the price and a overlay a linethrough using css but instead of using a visable characer use something that will produce just the linethrough. Not sure if the nbsp will do it. Maybe the minus sign with a linethrough. You may have to go to a fixed width font for both the price and linethrough to get everything to line up nicely.
Example:
$88.00 in black
------ in red overlayed using css positioning.
Play with the colors. Not sure what would look best using this technique.
Haven't tried this approach but it should work fine.