Yeah, I'd like to see SRP support as well, but until it gets into SCST, we won't see it in Open-E.
OpenE supports IPoIB so yes, you can push replication traffic over it. It *should* be treated just like another eth[*] int.
I would suggest you look into Fibre Channel if you have a budget for IB. You'll get great performance the the FC target is very stable. 4GB FB HBAs and switches are going for cheap on ebay these days.