SWR: Certified copy of marriage license

I need a copy to change my name on my passport (and I need my passport before mid-April!
We're going to the USVI and we want to do a day trip to the BVI, but my passport, although valid, is in my maiden name. If I go to the Huntington town hall in person (where we got our license) how long would it take to get the certified copy?? Any experiences you can share??
TIA!