Good morning Robert,
Collets as well as router bits are consumable items. When worn, you need to replace them.
Sadly, the 5362 appears to be no longer supported either by Porter Cable (or whoever owns them this week), or by the aftermarket replacement parts companies.
If you could find a NEW replacement collet for under $50.00, I'd consider that a win, especially if you like the router. If all you can find are used parts ... it is time to consider a new router.
The danger of worn collets is that the router bit will slip during cuts. I've had this happen on both my PC routers and my Makita plunge router and recently repaired my bench top due to the Makita deciding to cut through the work, the backing board, AND the bench rather quickly. I heard the motor loading down, and eased off the cut, but the router bit (an upcut spirial bit btw) went quickly into the bench top (grrrrrr).
My solution is to buy replacement collets, and always have a new one on hand. When a bit slips, both the bit and the collet are tossed, as I don't have time or interest in gambling on what really is an inexpensive consumable.