Once you figure out what your stock is, you can always sell utility barred birds...a lot of people are plenty happy to pay to get nice laying utility barred birds. You'll have to be very clear, on a sign, on the receipt, to state that these are mixed breed barred birds that will be utility layers.
I agree...if it weren't for the dark leg color, I would say Dominique, but wrong leg color. Leg color is right for Marans, and I think dark is dominant over yellow of the Dominique? (leg genetics still confuse me as they are confusing...and I just double checked SOP for Dominique...leg color should be yellow not white, they look white after washing out from laying).
Rose comb is dominant over single, so it could be a Dominique/Marans mix with the dark leg as Marans has grey/slate. Dominiques are technically cuckoo (white barring) according to SOP, so won't look as crisp as a Barred Rock.
Per chance does anyone has some signs of leg feathering....outside of leg down outside of toe? True French Marans have leg feather down the outside of the leg, down outside of toe (see my BCM photos below). However, there is a featherless type as well, and many Cuckoo Marans are featherless on the legs. If you see some vestiges of leg feather, especially in these barred birds, and if the barring isn't as crisp and nice but a bit blurry, then I would guess definitely Dominique/Marans crossing.
ETA: Or it could simply be a Dominique with wrong color leg (which means something got in somewhere in the background that shouldn't).
What did your stock person tell you they were when you got them for breeding?
LofMc
http://www.dominiqueclub.org/articles/APAStandardofPerfection.pdf
