Course Resources
Even though the Math Study Center (MSC) doesn't officially have anyone answering 307 questions, many tudors there are capable of answering them and happily will during slow period. (The 120, 124, 125, and 126 students have priority, though.) You can check their hours at the MSC information page.
The Center for Learning and Undergraduate Enrichment (CLUE) also have tudors and study time, and should have some Math 307 specific tudors.