AFAIK, the Williams spacer is only made in a single height/size, not in "an assortment".
IIRC, they raise a sight 1/4" (.250") - at least I'm pretty sure the one I had did.
If you have rifles that need higher sights, and the spacer block + your existing sight won't measure up, you're going to have to break down & buy the proper height replacement sights.
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