In new sights, you need a Marble's 63, 64, or 65 rear, depending on whether you want flat top, semi- or full-buckhorn. A no. 34W appears to be the right front sight, based on an old catalog that shows the same front sight for a variety of Winchesters.
Brownells has them.
If you want old sights to match the appearance of the gun, try Gary Fellers (817)346-9633 fax (817)346-0690
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