Most obstetricians have extensive experience in repairing these lacerations. I would go with an experienced OB.
In doing these repairs, I generally opt for general or spinal anesthesia, and the procedure should take about 60 - 90 minutes. POstop recovery is about 6 weeks, and I ask my patients to do warm sitz baths 3 times daily, and refrain from intercourse for about 4-6 weeks. Patients with this type of repair tend to do very well.
Since the doctor here hasn't answered any questions in almost a month, you should go to a regular OB and get a professional, in person opinion by someone who has seen the tear.
Did you have a planned, unassisted HB? I know you said it was a precip, but did a MW come and check you out after the birth? If so, she was negligent in not repairing the tear at the time, if its as deep as you say. Small, first deg. tears can often be left alone to heal on their own.
Show it to a doctor and see what needs to be done, if anything. Please post back. I'm always interested in HB, assisted or otherwise.