I cut WLS' from the side of a large white plastic (washed) Clorox bleach bottle, saved from Momma's trash toss.
Slice off the top neck/bottom & down one side, before flattening the white plastic out for marking/cutting.
The plastic can be pencil marked/outlined, around either the buttplate or the naked end of the buttstock (held vertically while scribing).
I use the BP, so I can also mark the screw hole locations.
I cut around the marked-out spacer, about 1/4" oversize, and punch or drill out the holes for the screws.
Mount the spacer on the stock, sandwiched by the BP & held by the BP screws.
Pare off (carefully) the 1/4" excess with a sharp knife blade (smaller = better).
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