Thank you for all the responses. The consensus is to try to find used controllers. The FLEXCUB solution is more elegant and versatile, but we have no xSeries machines lying around, and are looking for a cheap solution.
By the way, I understand that even if we can get our system to load via the Hardware Management Console, that would not be enough to support the stand-alone utilities such as DDR, should we need to restore disks from tape in case of a bad disk. Is that so?