Shimano M324 SPD pedals bearing replacement - worth it?

I have a set of M324 double sided SPD pedals on my gravel/general milling about bike.

One of them has developed a fair bit of play and noise - I assume it is the bearings.

Questions:

1. can they actually be replaced? I see some comments online that they are not replaceable but also replacement bearing sets for sale.
   
2. is it worth doing or am I better off just buying a new set of pedals?
   
3. How hard a job is it?
   
4. Can I just buy suitable bearings from any old bearing supplier? If I buy bearings as "Shimano Spare Parts" they seem to be about 10 or 12 quid for 62 (why 62?), whereas if I just buy 3/32 steel bearings I can get 100 for a couple of quid.
   

why 62?

31 per pedal?

Seems a very odd number? Especially as the diagrams I see suggest 22 per pedal - two sets of 11.

Hmm, some spares when they bounce between the floorboards maybe 😅

I have successfully eliminated play of a couple Shimano pedals by repacking/readjusting the bearings. Could be worth a try. Nice Sunday afternoon jobby.

I find adjusting pedal bearings a hellish job so tend to let them loosen until are beyond the point of saving.

If you are a more patient person it’s probably worth doing.

I admit you probably have to be a specific type of person. :-)

And have a specific type of #8, 9, or 10 socket wrench, since they usually take thin walled tools, and it’s a pita to tighten them in at the end.

There is a special Shimano tool for some of their pedals that is two, nested thin-walled sockets. Some pedals have a slotted or flatted (?) axle with an anti-turn washer that makes life much easier.

A wrench and sacrificial flathead screwdriver are my weapons of choice, but then I don’t service pedals for customers.

The special tool needed to properly adjust and tighten the bearing locknut is the TL-PD33, however this costs around £50!!! The higher up pedal models can be with opened/adjusted with normal wrenches and worst case a cheap plastic tool... I gave up on the M324 because of this