Hi Blcksoap.
This is my first time answering a question. You can edit the size of the prices by adjusting the CSS of the class.
I found the CSS of the class by using developer tools on google chrome (Cntrl + Shift + I) or use Cntrl + Shift + C and hover the area you want to identify the class.
In your case, it would look like this. So, on your theme.css (I believe), change the font size of the class “product_price.sale-price”. If you don’t know where the theme.css file is, go to theme tab, find edit code, then find assets tab, then theme.css.
I hope this helped. If it didn’t, let me know. Cheers
