He said it's going to be a street motor, doesn't need a Dart block for what he's looking for. Yes, the 511 block will be just fine......after you have it checked at the machine shop. ARP doesn't make main caps, they make bolts only.
If you use the ARP main bolts or studs you will have to have the main bearing saddles align honed because the ARP fasteners create more clamping force to reach "bolt stretch" or the proper "torque value" for that specific bolt/stud. This basically warps or distorts the main cap which requires them to be align honed to make them round again and bring them back into tolerance. For a street motor you could re-use the stock bolts if you're going to keep the power reasonable.....me, I use the studs and align hone, then you can do anything you want.