Yes I have in the past, it is a safe way & price is reasonable to get marriage, birth and death records when you live too far to go there. Your dealing with old records, so I would go vitalcheck, I don't think you will find an actual copy of the record in any genealogy bulletin, just indexes and what ancestry has.
In the past you had to go to courthouse, order the record & pick it up the next day, if your on vacation like I was that was OK, I'm sure that has changed with every thing being microfilmed/digital. I don't know if the Baton Rouge Archives would have marriage records for 1865 from St Tammany Parish, that would be another source to look into. Good luck in your search.