Dazu hat Rob was auf seiner Seite stehen, ich kopiere das mal hier rein, hoffe das ist OK (Quelle www.monsterwatches.nl)

The “made in Japan” versie is more expensive. Mainly because it is harder to get. Some differences (my opinion):
100% Japans: parts and assembly, so a “real” Seiko.
Hard to see: sharper grip on the bezel and sharper transition between polished and brushed surface, it seems that the workers that make the made in Japan version put just a little bit more effort in their job.
Easy to see: “made in Japan” and “21 jewels” on the dial, “Japan” on the case back. But also inside on the movement.
Alignment of the dial ring: this is a well known issue with the SKX007. The dial ring is a loose part, it lies on an edge in the case, and there is a “nipple” that keeps it in place. But the nipple is smaller than the hole it goes into, so the dial ring can move a bit. This issue appears equally in the K and the J version.
I try not to sell those! I keep them aside and correct the aligment when I install sapphire.
The bezel is a part with a function (how long you are submerged). Being exactly at 12 is not its function, and Seiko does not care. The way the watch is made, a complete bezel is pressed on the case) almost prohibits the markings to be at 12: there are too many variables: click ring, indentations on the bottom of the bezel, how the bezel insert is placed in the bezel). If you want a perfectly aligned bezel, the insert must be placed after assembly of the watch, and that will result in a much more expensive watch. I can do that, if you ask for it, but will charge 25 euro for it. I have to remove the bezel, take out the insert, press back the bezel and re-install the insert.
Technically the J and K version are identical! They are both checked by the same Seiko quality standards. The PU-strap and Seiko jubilee are also the same. When I make a modified SKX, I usually start with the K-version becuause it is cheaper.