I do not know where you can get red lenses for the stock lights, however you can paint the amber lenses with 'testers transparent red' paint. I did mine a couple of years ago (when I changed to running lights) They look nice and you cannot tell that they are painted. BTW you paint the inside of the lense only.

05 speedmaster - 1100cc, 11:1 racing pistons, Carillo rods, thunderbike cams, ported and polished head, 2mm over intake and exhaust valves, Barnett kevlar clutch, scepter pipes, oversize manifolds, 45mm HSR's, TTP stage 4 firestarter