I'm looking at the diagram for rear suspension components through Honda eStore, but it's confusing because there could be 1-4 part numbers associated with various bushings and other components (not necessarily due to differences in country of manufacture or California specs).

Instead, the brands are different.

So for bushings, you choose from Yusa or Hokushin.

For "Rear Stabilizer Spring" there's Rockwell or Nippon Hatsujo.

Just curious, why is this? Is one like an original, original part and the other related to some later OEM styling (like an OEM replacement part)?

Sometimes different brands within the OEM parts are interchangeable, but other times they are not. How do I determine what to order?