Municipal Archives don't have a lot for that early - there was no legal requirement to register marriages and most folk just did this at church. You're best bet is to try churches of the right denomination in the area they were most likely residing. You can usually rule churches out if they were consecrated after the marriage date but you might need to do some digging for where records might have been moved to if a church has since closed. I've used this scatter gun approach in the past and come up trumps. Advice - grease the palm with each request - it helps offset their time/costs.