I took some photos to compare an original pre-war aluminum Wehrmacht mess kits, with some postwar versions. The most important thing to understand is that there are postwar mess kits that are identical to real ones, as well as some that are very close, and some that are more different.
In the above picture, in the top row, the one on the left is an original pre-war German Wehrmacht mess kit. The one on the right is a postwar Austrian mess kit. It has a postwar maker and date stamp, and the lid of the mess kit is perhaps a fraction of a centimeter taller than the original (although this varies somewhat from maker to maker on originals). Visually, without inspecting the markings, the mess kit itself is indistinguishable from the pre-war Wehrmacht model. The paint is the wrong color. Stripped and repainted, in my opinion, this is perfect for use.
There are two other postwar styles that are identical to the pre-war Wehrmacht kits, that I do not have to show: some 50s dated German ones, some of which were made by some of the same factories that made them for the Wehrmacht; and postwar Romanian issue mess kits.
Back to the group picture, the second row: on the left is a Soviet mess kit from the 50s. This is very nearly identical to the first Wehrmacht model, with two exceptions. I have included photos that show these differences in detail. Firstly, it has three rivets instead of two, holding the handle on to the top part. It also lacks the three small impressed measuring lines that were on the front of the bottom half of the kit. The most common wartime Wehrmacht model also lacked these measuring lines, but these had a steel handle on the top part, instead of the prewar aluminum handle. Original used and issued kits are very often found mismatched, even when they appear to have been used that way during the war; it’s not at all implausible that a soldier in the war could have used a wartime “bowl” and a pre-war “lid.” There were no Wehrmacht kits with three rivets on the handle; whether or not this difference renders this type unsuitable for reenactment is subjective.
On the right in the group photo, in the second row, is a “Frankenstein” kit put together with a postwar East German NVA bottom, and a postwar West German police lid. The East German kit had a lid with no strap retaining loop, which in my opinion is visually and functionally so different from the Wehrmacht kit to render it unsuitable for reenactment use. The bottom, on the other hand, is very close to the Wehrmacht type. The difference is on the cast attachment fittings for the wire bale. The Wehrmacht type is riveted on with two small rivets. These rivets are not visible on the East German one. The exact size and appearance of the rivets varies on Wehrmacht kits, but they are always there. The top of this “Frankenstein” kit is a from a postwar West German kit. The bottom is in my opinion not suitable for use, and I will show it later, but the top is identical to pre-war Wehrmacht issue, except for the markings. I used to use this “Frankenstein” kit myself, before I found a postwar Austrian one to use.
Of the four types of mess kits previously described, we would allow any of them to be used in Sicherungs-Regiment 195, though we discourage use of original kits as they are historical objects with a collectible value, and we cook with ours over fires and use them at every event; I would cringe to subject an original war relic to that kind of abuse. The mess kits on the bottom row in the group photo have parts that I would not allow to be used in my unit. On the left is a Russian one, a type used from the 50s into at least the 80s (probably even later). This has the aforementioned three rivets on the handle, on the top. On the bottom part of this kit, the attachment fittings for the wire bale are totally different from the Wehrmacht versions. This difference on the bottom part is too obvious for me to regard it as usable. On the right in the bottom row, is the postwar West German police kit lower half. This also has the Russian style bale attachment fittings.
Where to find these? Quantities of postwar Romanian and Austrian mess kits pop up on eBay from time to time. I keep an eye on the various Facebook sales groups where reenactors sell items that are no longer needed, as there are many of these mess kits in circulation. I also look at Soviet buy/sell/trade pages where the Russian ones that I regard as usable (with the German type bale fittings) come up every so often.