Originally Posted by MauriceMoss

The features on that frame are relatively generic so they're consistent with a few different builders. However, that serial number on the drive side rear dropout makes me think this is a Haral (La Motte-Servolex/Chambéry). Haral used to stamp numbers on the drive side rear dropout, either on upper or lower parts, in a really small point size.

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As for tubing, I suppose Vitus 971/980 is a possibility although, of all the Harals I've seen, it seems like Vitus is the least common type of tubing. Around the time this mystery frame was made, they were often built with Excell tubing, so that would be my guess here.