Here are a couple of photos of the 1804 Streicher instrument in Leipzig (rebuilt in the Streicher shop from an earlier Frère & Soeur Stein). The iron gap spacers are visible.
Here are photos of the 1803 in Nürnberg; it has a single wooden gap spacer under a course of dummy strings in the middle of the string band. The legs are not original, and should look like the 1804.