Pismo is the only thing that can mount AviSynth scripts.
Pismo is actually the exception here, as mounting typically has to do with devices - HDDs, partitions, optical drives - or pseudo-devices (like ISO images). Pismo simply extended this concept to AviSynth scripts is all.
So no, under Linux you cannot mount AviSynth scripts. You can, however, mount ISO images, CDROM drives, varying types of filesystems on different partitions, and so on.
If this is concerning using the files while editing with a native editing program (PiTiVi, kdenlive, Cinelerra, or what-have-you), you'll probably just have to go back to old fashioned clip-cutting, making sure to stick to formats they'll recognize - like HuffYUV. Fake AVI methods would probably only work if your editing program were also running in Wine, and possibly not even then.
If this is about final compression, then you can just run Windows builds of x264 or ffmpeg or so on in Wine, since Windows builds of those apps usually have AviSynth support autoenabled.