It also depends on if it has the "early" white button & silver rim around the edge of the lens (painted on back) - which are worth much more than the later plain clear lens & black button late variety.
Original West German Hella black button ones in excellent condition might be in the $25-35+/- range, while the early white button with silver rim West German Hella might easily exceed $100 in just good condition, as Mike Fitton said above.
Post some pix of what you've got, so folks can help out.
There is also a topic in the O&H Forum where Dave K. posted pix of the various makes & types of early lights, which will help you ID yours.
You probably should repost the question on what's it worth in the Garage Forum, & then repost the FS ad in here once you have the help with the price.
Tom
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