Pachmayr does not make a pre-fit for a Ruger #1, AFAiK. Yes RED decelerator pads are available from Brownell's. I don't like to put them on #1's because they require that the stock must be cut... Unless you are 7 ft tall and have gorilla arms...
I have one on a #1 that was already shortened when I purchased it. Looks real nice. Hope this helps...
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"It is far better to be alone than to wish you were" - Ann Landers