MSA & HSZ batteries - AA NIMH trick-swap available?

Has anyone ever found a way to beat HP at their game of putting ridiculously low-quality proprietary batteries on their RAID controllers? I had no end to trouble with HSZ batteries dying back in the day. Nowadays I still have an old MSA1000 with similar looking batteries. The part numbers are 401026-001 (right) & 401027-001 (left). Has anyone ever seen some kind of caddy or carrier that can replace these ? They are very oddball in shape. They clip onto the boards with plastic friction shields. However, there is greater clearance on the MSA1000 controller board than is needed for these batteries. Since it's 4.8v I'd love to replace this with qty=4 1.2v NIMH AA or AAA batteries. They'd probably last longer anyway. There is nothing magical or special about these battery packs, correct? If I find something mechanically workable and with matching voltage can I not use that as a replacement? I really don't care if I have to solder it on. The folks who sell replacements for these online tend to not say if they are new, used, tested, etc... I don't trust them enough to send them $40-$120 for the replacement. -Swift