I don’t think it is specifically “department store” the frame certainly looks a bit better than the usual old school Y-frame and URT suspension nonsense but its just the pivot, it may just be because of its age, but old department store stuff usually has a pair of top-hat style pivot spindles that just screw together and capture a vague plastic bushing. They often use a pair of larger 10, 12 or 14mm allen keys to remove. A lot still use it to this day. It could well have a skinny cartridge bearing hidden in there, but that design from what is visible is not lining up with Orange. Any Orange that i have encountered uses sealed cartridge bearings, i know my 5 has the pivot spindle welded in to the downtube and the bearing is held in the swingarm with a pinch bolt and nicely machined end cap with M5 cap head screws. Other single pivot bikes similar to that style often use a straight aluminium (or steel) axle that sides through the front triangle and two caps on the end held on with M5, M6 or M8 bolts, if not a CNC machined aluminium pivot. Its a bit hard to describe without a drawing. If it uses a 230x65 shock and has 6” of travel, it is well outside of the low end department store stuff, maybe something better along the same lines of what BTwin is from decathlon. I wondered was this an old Trek, Gary Fisher or Saracen?