what rotor seals are needed in a standard rebuild?
 

mazdatrix says all these come in an 800 dollar kit.

do you really need em all?

Apex Seals - yes
Apex Seal Springs - yes
Corner Seals
Corner Seal Springs
Corner Seal Rubber Inserts (where applicable)
Oil Control Rings
Oil Control Ring "O"Rings
Oil Control Ring Springs
Side Seals
Side Seal Springs.

they also have a full gasket kit for 350 bux...and a plain engine gasket kit for 150 bux.

you could get it cheaper at revolution rotary or try mazdaformance. What you need depends on what you want to do with the motor. You could reuse side seals, corner seals etc if they are within spec.

i want to replace only the ones that are more prone to failure (ie, the old worn apex seals on the rotor that didnt blow)

The seals you need really depends on the condition of your motor.

Quick ?, I need to replace the coolent seal on my engine. The rotor seals, and the apex seals are fine. Which kit would I need. Thanks

its 'usually' a good idea to replace the apex seals on any engine that has more than 30k miles..or at least the seal springs..

btw, you probably just need a gasket set. they're about 150 bux for the engine essentials