It was late (for me) when I posted that yesterday, so in the clear light of day here's a bit more (from memory) ...
I'm pretty sure that the H-23 is the weatherstripping base, sometimes numbered GA-23 or GA-H23 ("H" was used on items sold under the Stanley "Handyman" banner from the late 1940s to the early 1960s 0n power tools, they often had orange ratings/model plates as opposed to the blue and later black plates of the industrial lines - but were otherwise identical). It was designed to be used with the router motor installed and a narrow grooving cutter fitted to produce the weather stripping groove near the edge of a board. The Stanley side fence is actually quite small and I've seen them with the original fence replaced with a much larger aluminium plate a few times. Unlike the planer base the front skate is non-adjustable and the cutter housing is much bigger (to accommodate the grooving cutter). They still have their uses, but because the motor hangs below the sole of the body that unfortunately cannot be used for routing grooves or beads across wide boards, which is a pity. The planer (possibly GA-H257 the longer model, or GA-H142 the shorter one) has a far more versatile fence which tilts up to 45 degrees and has, as already mentioned, an adjustable front skate. They were generally sold with a spiral steel cutter which has a 5/16in bore to fit onto a special shaft (also supplied in the kits), but those cutters haven't been available for many years and the AFAIK only spiral cutters you can still get, and then only rarely (for the Rockwell/Porter-Cable 126/226 Porta-plane), are unfortunately far too large in diameter to use in the Stanley planer bodies. Owning both a Rockwell Porta-plane and the Stanley planers I have tried.... and I'm still searching for a suitable replacement. TBH planers don't work at all badly and produce a really good finish because of the spiral cutter, well up to the standards of my modern Festool spiral cutter planer, but the depth of cut they can handle is tiny because with (in the case of your H-39) only a 4A (450 watt) motor they don't have a huge amount of power to play with. The cutters are also impossible to resharpen without Stanley's sharpening attachment.
I actually have an H-63 builder's kit in storage which I could look out if you're interested, but perhaps more importantly I still have some of the original early 1960s manuals if you need copies making (but as I'm currently working away from home it may be a week or three before I can access that stuff)