Schlappen is not going to replace marabou as it's totally different. Pretty sure I know what your looking for and that ain't it! It's nothing more than longer and wider hackle feathers.

Just a warning about this and I know some guys are doing this method to keep from tearing off the feathers for the stem, but think about if some fish, snag or what ever, maybe even a gar cuts that stem; you jig is done even if it the first cast. Not sure why you don't think that you get pretty much the same thing tying marabou the regular way. I mean once it's wet all of it will be the same.

As far as selection of materials I don't think anyone has as many items as Bob Marriott's...
Bob Marriott's Fly Fishing Store - Product Catalog - Turkey & Marabou

Just look through the feathers and see if what they have will work. YOu can call them to ask most anything for help and they have good service. I know it's retail, but they carry so many items you can't get with out having some kind of account with every supplier out there.

Or maybe the Extra Select marabou that Hareline has will do, I just have never used that method for my marabou and doubt I ever will. I have bought a bit of the Extra Select Marabou and it's really long and nice, but packs are small since I usually buy my marabou by the OZ at least and some by the pound. Bob's also carries pretty much all of Hareline's stuff plus lots of others.

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