Martha Stewart/Avery has 1" & 1 1/4" & Staples has 1" & 1 1/2", but I've recently heard of Levenger Circa discs having more options (both size & color).
And just to clarify, these are my own opinions--I don't work for Staples or anything, honest! LOL
Links I mention in the video:
Prayer Starters by Jennifer Kennedy Dean
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