I came across this company who stock a range of high quality but cheap front surface mirrors and lenses. They sell also cheaper firepolishd lenses and some high quality fresnel lenses. They hold all the parts in stock over 2000 parts ready fr shipment worldwide. They will also ct parts to yor specific size, so very helpful.
www.knightoptical.co.uk
the cheaper but qulity mirrors are at http://www.knightoptical.co.uk/acatalog/MirrorsPlanemirrors-General-purposeGrade.htm
www.knightoptical.co.uk
the cheaper but qulity mirrors are at http://www.knightoptical.co.uk/acatalog/MirrorsPlanemirrors-General-purposeGrade.htm