Check Parking Lights - Time to change Angel eyes?

[DrunkenNinja]

Recently got the "Check Parking Lights" message on the dash, the (2) Angel eyes on the right side are not working and are the yellow OEM type.

I did some reading and thought these looked good:

ANGEL EYES

1st question

Do I need to buy (two) sets of these or just one?

Reason I ask is there as there are two Angel eyes on each side of the X and one pair are given in the box.

I want them to match on both sides so will I need 4 bulbs (2 sets)?

2nd question

I don't see the angel eye ring on these lights, how exactly do they work?

To further confuse things I see items like these for sale:

HALO LAMPS

Maybe the the above what I need? I see I get four.

I am well and truly confused, any help form someone who has changed these bulbs in the past is greatly appreciated, I am fed up with my Indy overcharging me and it seems like a simple fix.