I am planning on getting some new o-rings for my oil cooler on my 84 GS to fix a leaky oil cooler, but I noticed that the price for them is astronomical on atkins/mazdatrix compared to that of Black Dragon ($20 vs $3). Is there something I am missing here?

I am using part number 3-5431 for the Black Dragon o-rings. Are these the correct ones? My intuition leads me to believe an o-ring is an o-ring but just wanted to check with the brain trust.

http://www.blackdragonauto.com/icata....aspx?Page=113 (part is at bottom of the page)

I have also noticed a drastic price difference between oil pan gaskets between atkins/mazdatrix and black dragon... What gives?

 

for the stock cooler, o rings are just o rings. the Mazda supplied ones come from somewhere, and Mazda Japan, marks it up and sells it to Mazda USA, who marks it up and sells it to a dealership, who marks it up and sells it to Mazdatrix/atkins who mark it up and sell it to you. not a recipe for an inexpensive part.

vs ordering the closest imperial sized o ring

i don't know about oil pan gaskets, silicon sealant works better (its what the factory uses)