There are a couple of HP-41 repair services linked in the HP-41 section at the bottom of my links page given in my signature line, but both of them are having problems now, apparently from bad health, and are not responding. (I give that info on the links page too.) Hopefully someone else will take up the banner and service these and keep them running for many years to come. If I had your problem, I'd at least get the flex circuit replacement I linked to so I'd at least have it on hand for when I find someone else I could trust to do the job, or for if I started feeling ambitious. The battery corrosion is the main and possibly only reason this part was made available.