The Coleman 9H was made for the 1936 model year. It has nickel-plated legs, a cast iron burner with "Hi-Power" aka "Wind-Proof" burners instead of the Band-a-blu burners on the more deluxe models. It has an Everdur fuel tank (a Copper alloy) and the pump has a pinned stem to hold it back in case the pipped check valve failed, since there was no positive shut off with this arrangement. (Some of these have been replaced over the years with the more standard pump/cv.) The 9 series is a medium sized stove compared to the larger model 3 and 413's. The Everdur paper sticker on the inside top of the lid has fallen off, only remnants at the top remain. Some of these stickers are dated. To help identify a 1930's Coleman stove that has been repainted or is missing its identifying badge, try this Field Guide: Stove Field Guide - International Coleman Collectors Club
I wonder if a photo exists of this earlier ‘pipped’ check valve? Slotted for removal/installation, presumably and since you say they were often swapped for the improved arrangement, having identical threads to the steel check valve? It would need to be capable of disassembly too to replace the ‘pip’ seal if necessary, or maybe the whole valve was discarded and replaced. Enclosed pump tube with the check valve not immersed in the fuel and an air outlet tube arcing up to a point in the air space above the fuel, I guess.
Here are some photos of these check valves. The "pipped" (223-538) and the ball bearing (242B538) versions are interchangeable. The 223-538 check valve can be serviced, but typically when a stove or lantern was taken to a Coleman repair outlet the technician would simply replace the old style check valve with the new style and swap the pump/pump cap as well. The 242B538 requires a pump with a shaft that screws into the check valve, allowing air to flow into the fount and to prevent air leakage when tightened. The 223-538 can use either pump, although the air stem has to be removed from the newer style pump. I once bought a 242 lantern at an estate sale that had the newer check valve and fortunately the original pump, which is hard to find. There was no way to close the check valve, it just relied on the ball bearing in the check valve to seal the fount pressure. It actually worked pretty well...unless residue built up inside the check valve. I replaced it with the original 223-538 check valve. edit: this stove came with a used check valve (and generator) and a note saying "Stove Check Valve - they don't make the replacement part anymore (save spare)".
