I don't know what is going on with the hydraulic lines as far as their function, never seen anything like it. The installation along the frame looks original to me with all the clamps and well formed tubing.
The springs and other hardware look like very standard stuff, even to perhaps being the same as light truck parts. None of those parts are really critical for dimensions, I would be inclined to talk my local parts counter man into bringing out several kits and look through them for the parts that match. It might be necessary to buy a couple kits to get everything. The other route would be to do directly to somewhere like Brake and Equipment Warehouse in Minneapolis,
https://brakeandequipment.com/
