Tyga do have the left and right crank seals in stock - look in the MC28 Honda parts section. The center seal cannot be bought seperately as a service part, its an integral part of the center main bearing which can only be changed with a crank rebuild. Mixalisen can source new bearings for a crank rebuild if you want to go down that route, otherwise you need to buy a new crank.

If however, you are only interested in the left and right side crank seals then they are readily available from Tyga (for example) and are easy to change when you split the crank cases.
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