Speedometer Repair - Referral Request

I have a 1968 a body speedometer that I am pretty sure needs to be repaired. Makes an awful racket and jumps all over the place or just reads zero while driving. Replaced the cable (which was not in good shape) but it did not fix the problem. Pretty sure the speedometer needs to be repaired in some way. Been watching for a good oem used one but have not been able to find a 1968 150 mph unit. Have seen a couple other posts on fabo under the topic of speedometer repair and some are advising it is more cost effective to repair than buy a replacement. I would like to stick to oem.
So, I am asking for advice on what businesses people have had success with repairing their late 60's mopar speedometers. The only one I have heard of a couple of times is Deluxe Speedometer in Denver- any feedback on them would be good. I am in the Seattle area of Washington state and don't mind shipping it out if that is what it takes to get it done right.
What does everyone recommend?

You checked the speedo drive gear, right?
They can strip off the plastic teeth.