conversion - Convert Word 2007 equations to Microsoft Equation

I am about to submit my article to one of the scientific journals.

However, it is very likely that they would only accept files in .doc, whilst my article is written in .docx and tons of formulas are in native Word 2010 Formula format. Saving those formulas as images could work as a last resort, but I don't think the guys in the publishing office will be happy with that.

Is there a way to convert new Word formulas to the old Microsoft Equation format without too much pain?

Thank you!