Why not looking into the entry level storages, for example HP MSA 1040 (limited to max of 3 enclosures) but cheap , the 2040 is more expensive but salable.
If it's an environment that will not scale i'd go for the 1040 and 8/8 fc switches to connect the 3 hosts, that should be a cost effective solution. an advice not to ignore the disk performance, don't only consider the nearline and go for the cheapest, you might need that performance, depends on the workloads but just keep that in mind.