Short story, yes.
You can- replace the spool or eBay seller mrgenesse parts out Medalist reels, or Bob Selb at classicflyfisherman.com makes a replacement metal latch cover as does Dan Hill formerly onepfoot.com (I have an email for Dan if you PM me)
Any spool for the appropriate reel should fit from the first Patent drag units end of production, I believe.

It happens to some of the early plastics. Some latch covers are fine, others have just disintegrated. I"m not sure how much is due to the chemicals they were exposed to and how much was just the variation in that new material.

Mine is still functional. Just out of round and wavy. This particular reel is in original box and never been lined.

Nice that would be a horseshoe latch model?

Sorry looked through my Medalist spare parts and found no plastic latch covers. I remember now sending a couple to another on CFRF a year or two ago. Maybe another board member has a spare from an Akron reel they'd be willing to donate.

I agree with Bulldog that the plastics in the 1940's Medalists deteriorate vigorosly. My experience with the plastic handles has been that the original pyralin amber colored handles on the 1930's Medalists hold up very well. Also the swirled plastic handles on the Gem Reels hold up. The formulation must have been changed in the 1940's as ivory-colored handles were introduced and aluminum spool release covers and aluminum drag adjusting knobs were replaced with plastic. I have seen too many spool release covers, spool handles, and adjusting screw knobs deteriorate from the 1940's era reels. By about 1950 the problem was solved even though I think the USA made Medalists until 1982 still used the same nitrocellulose-based plastics. The spool release covers and handles from the vintage 1950's reels actually improve in appearance with age. The plastic is Nitrocellulose based, 1st introduced in the late 1800's as a substitute for ivory . Dissolves with denatured alcohol. Very flammable. The nitrocellulose based plastics were used on photograhic film before World War 2, a hell of a fire hazard. ( my info on pyralin is from Wikipedia, this Pandemic has sidelined me to too much useless information) (Also I am from Rochester, the George Eastman House is here and the storage and preservation of old motion picture films is important, Eastman also started a company here that actually manufactured film) (For those too young to remember photograhic film was a way we used to store images)

Thanks for your support, but I believe the differences were entirely batch-to-batch.
Resin and hardener compositions varied by batch, and then mixing the two also varied - to get swirl, you kind of choose up front to not mix thoroughly.
I bought a NIB Gem from 1942 that the swirl knob had melted in the box - it was a great buy, and added OnePfoot knob.

Bamboozle, if you haven't already, should add your link to the sticky thread.

way cool, bro

especially automotive lubes - long-term, they can break down and release naphthenic acid.
All those crazed green erinoid handles from before WWII got that way from this lube decomposition, and the green was copper salt from the spindle screws.

The same process probably attacked the lead finish.

Let us know how the transaction goes on the Young Pfoot sticky thread.

Previous ownership wasn't as easy to order and receive from as original ownership so it will be of interest (at least to me) how the current ownership handles things and the quality compared to the OnePfoot originals if you have any to compare to.