Do you have a specific variety in mind? Black Copper? Wheaten? Cuckoo? Where are you located? I have some pretty decent Wheaten Marans, they are from Buddy Henry's birds. I don't think he is breeding them any longer but was reputed to have pretty good stock. Mine lay a huge quite dark egg and are laying right now. I do not ship eggs, just doesn't seem to be worth it, but do ship chicks, I should have some chicks a bit later in the spring. PM me for details if interested.
I have no idea what Marans eggs are selling for right now. When I bought mine (hatch was horrible) I paid 7 dollars per egg plus shipping. Expensive way to get a start in my opinion. Chicks are much better odds and not a lot more costly