SOLs are a state test, not one given by the school. State regulations are not bound nor dictated by your IEP.
There are accomodations that can be made if there is a documented disability. However, for a reading test, I'm not so sure if that would be considered a "reasonable" accomodation, which is all the IDEA (a law, Individuals with Disabilites Education Act) requires. Considering this particular SOLs is measuring that you can read and comprehend on a basic 9th grade level, I'm not sure that allowing someone to read to you a reading comprehension exam would be a considered a reasonable request, regardless of what your IEP states. An IEP does not override state laws or regulations--which sets the requirements for a person to obtain their high school diploma. Since the exam is making sure you can read and comprehend on a 9th grade/adult level, and you're only at a 4th grade reading level, it isn't fair to others to have you pass an exam which you wouldn't be able to otherwise as you cannot do that without fundamentally altering the content.
So, in summary, the SOL may have one set of rules and your IEP gives another. But for the SOL, you're bound to the SOL rules. If the SOL reading exam says it cannot be read to you, then it cannot be read to you, regardless of what your IEP states.
What would be a reasonable request would be an untimed exam, which is common and widely accepted as okay for a person with a learning disability.
There was a recent lawsuit in regards to reasonable requests. And in reading that decision, the exam board granted a reasonable accomodation, but the test taker wasn't happy and wanted more of an accomodation (the breastfeeding MD/PhD woman who was looking at taking the STEP II of medical licensing). It was determined that she had been provided a reasonable accomodation, and by giving her the additional time she was asking for, it would fundamentally alter the exam and it wasn't fair to the other candidates, so no, her request will not be granted.
(And if you were wondering, yes, I am disabled.)