3 1/2" X 5 1/2" (86mm X 135mm)

(skirt incuse) EST

{Maker unknown}

Picture courtesy Bob Scafe

3 5/8" X 5 1/2" (89mm X 135mm)

(skirt side recess embossed)

{Maker unknown}

Picture courtesy Bob Scafe

3 5/8" X 5 3/4" (89mm X 141mm)

No markings 

Picture courtesy Bob Berry

3 5/8" X 5 7/8" (90mm X 145mm)

No markings 

Picture courtesy Tomas Merski