I have been searching the web for some history of pressure suits in Japan and found nothing much. Do they make pressure suits for their fighters?

Some points:

The Apollo suit (A7LB), including the backpack, weighed 81.8 kg (180 pounds).

The Shuttle suit, including the life support system, weighs 140.9 kg (310 pounds).

The USA's current prototype planetary surface suit is the Mark III which weights 95.5 kg (210 pounds).

20 kg is 44 pounds.

A week is a really long time compared to the length an Apollo or Shuttle astronaut has spent on an EVA (8 hours?).

On Mars you might be able to extract CO2 and crack oxygen out of the atmosphere to make the PLSS weight less and allow week long or even indefinite length use of the life support. Depending on the system used and power consumption. I suggest looking up "Oxygen Free" if your interested in that.

The Moon has no real atmosphere and a huge issue with very very abrasive dust. How would they extend the life support for a week? Scrub the CO2 and reuse the air? Use liquid oxygen? The Mark III does the latter and uses it for cooling as well.