1) The regional alternative to ‘upper leather’.
c.1424 pro aptacione duodecim parium de les over leders jd ob, York
1458 unum daykyr de over ledder, Wakefield
1627 without mixing the overleather part of neats leather and part of calves leather, Beverley. The inference is that only the hide of a full-grown beast was of the right quality.