When looking for the J-frame grips, take special note on the back to where the hole for the positioning pin is drilled. As said, the earlier ones were about 1/8" shorter, making the position of the hole that much closer to the bottom edge of the grip. The Baby Chiefs pictured by the OP is a J-frame with an I- frame size grip and smaller trigger guard than the later Mod 1953 J-frame had. That being said, I think the 'shorter' J-frames would only have been made for about two years (but the I-frame stocks will fit).
Here are pictures of the grips/Pre-Magna Service Stocks for the Chiefs Special pictured in the original post:

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GrinningDag, please post a couple pictures of your Chiefs Special. We really like pictures, and we can help assure you get the stocks you seek.