There's another difference between .22 LR & .22 WMR: bore size. LR is .222" and mag is .223.

Reports differ on the accuracy of shooting the smaller round in the larger bore. I myself have had a couple of firearms (Ruger Bearcat revolvers) with interchangeable cylinders. One was accurate with either cartridge, the other sprayed .22 LR in what charitably might be called a decent shotgun pattern. The reports I've read indicate others have had the same issue with other firearms. Even if you could fabricate some kind of a chamber adapter, there's a chance the .22 LR may rattle its way down the barrel.

A better approach is to ask yourself to what use you're going to put your Mdl 24. If you really anticipate needing the .22 Magnum for larger game, then that's the caliber you get. It costs more, is available in limited choices, but it is more powerful.

Otherwise, get a .22 LR: it's (literally) the most popular caliber in the history of the world, ammunition is readily available everywhere (and often at sale prices), there are over 100 variations, including some target rounds that will knock out the iris in a squirrel's eye at 50 yds.....