i would recomend a cromoly flywheel like a jun or toda unit for durability reasons. i got mine for like 400 on ebay.

800 seems like a lot for an exhaust. i would put that kind of money towards getting the engine dowel pinned, street ported or getting new apex seals and springs, especially if the car is being built for competition and you already have an aftermarket exhaust. do rotaries benifit much from swain coatings, thats something else that you can look into.