Definitely give it a shot, I know with my online classes changes are harder to make in texts because we get our course shells from instructional designers, but at some of the schools I've worked at they've let me determine the course content, at the very least try this:
Dear Prof X,
I know that it is hard on you when students need to wait like me to get a text weeks after the course has started, even if we cannot pilot this as an alternative text, perhaps we can work together to adapt this text to allow students to keep up until financial aid is available.