There are about three styles of scout packs that have been in common use as well as a deluxe version of yucca(1329) that is better suited to a packboard or frame, than the most common scout pack, the 574 yucca pack. The official frame was the Cruiser. Two other packs are the ultra basic haversack and the camper or three pocket model. Those four models are all Diamond brand packs and all have permanently attached straps that are stitched and riveted with a reinforced leather patch. If any of those models lack straps, they have been removed or its a different model.
There are two other less common packs the 1307 D by Diamond and an early one called the Trapper Nelson, both are designed to remain on their frames. The Trapper Nelson is much more rare and looks different from the 1307 which at first glance looks like a yucca. Most 1307 models have a zippered outer pocket and a red Scout seal rather than the black one found on most Diamond brand packs and a handful of others have model numbers you aren't likely to see. As these models are designed to stay on their frames they have no straps or only have straps for attaching to a frame.
Being canvas, any of the old Diamond brand packs are easily modified and maintained as long as the cloth isnt rotten. If you have a bag needing repairs or something modifed any luggage repair shop should be able to help.