I think before I'd jump into the camera I'd compensate 1 stop and see how that works. Sometimes, more often than not, a simple repair will go awry and end up costing a good deal more.
If memory serves I believe my 3.5F meter was approximately 1 stop different from my Luna Pro CdS meter and it worked fine for the 6-7 years I had it. I think I used the average between the two meters as a fudge factor and I sure liked the results. Could be your meter is just fine and calibrated the same as my old 3.5F.
Until it's completely dead I'd apply the "if it ain't broke, don't fix it" rule.
Just my .02,
Fred