Bergen Rucksack

• Most correct for this time frame would be the 72 Pattern Arctic Bergen, commonly called the SAS or Arctic bergen. It is a butyl nylon, external frame rucksack with a 120L capacity.
• While these can be found on ebay fairly regularly prices tend to be high and you really only want this if you are a serious gear nerd. With shipping they usually run around $120. They can be gotten much cheaper if you can find someone to bid for you on bergens that are listed as "only shipped within the UK" since it's the overseas bidders that drive the prices up on these.
• Also, hugely popular during this timeframe is the civilian Berghaus Cyclops. The later PLCE bergens were nearly outright copies of this bergen.
• The PLCE bergen with side pouches is easier to come by, better on your back and also has 120L capacity. OG or DPM should both be readily available. There are two sizes for this ruck. The short-back and long-back both are 120L. The long-back is narrow and tall, the short-back is wide and short. The long back is best avoided as it interferes with your belt kit on all but the tallest of the tall. Say no to Web-tex and other cadet grade brands.
• The Pattern 58 large pack should be avoided at all costs. It is completely useless for anything but the lightest of loads and even then it barely manages. You'd be better off stuffing the items in your pockets or a ressie bag rather than this pack.