Hareline Sells these tail pieces in mixed colors ro a very reasonable price. Try any shop that sells Hareline products for theirs.
Here is a link to one of their packs, but just know there is no telling what colors are in each one. Mine I combined like colors so not as sold. You can just buy what ever colors of the whole tails too!
https://sep.yimg.com/ca/I/yhst-13789...498_1214741311
Found one that sells these combo packs.
https://www.caddisflyshop.com/squirrel-tail-combo.html
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