Although there may be exceptions, seals for outboard motors are generally standard industrial items. Measure shaft diameter and diameter of recess seal fits into and thickness of old seal. Seal catalog is set up by shaft diameter, Then you choose a seal that fits the recess size and thickness of seal. Within each area are several seal variations. There will be a preferred choice that will be the least cost for most applications. 1050s era was pre metric for almost all producs made in USA. If you have Chris Craft part number it most likely can be cross referenced to the industry standard part number. If you work on old machinery you will find a working knowledge of seals and bearings useful.
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