I have seen true Aldis scopes in good/great condition go for over $1000. I can't say I'm much of an expert on these things. If it is a post war Aldis lookalike, and the internals are functional, I would guess a couple hundred dollars... though hopefully someone with a better idea can chime in.
---------- Post added at 08:45 AM ---------- Previous post was at 08:44 AM ----------
If you are selling, I may be interested if the optics functional. Hopefully someone with some more info can grace us with their presence.