Colored lenses would reduce your light output at least 25%. Are you sure you want that?
Many of those aftermarket blue bulbs actually emit less light than stock ones (not the super bright ones on late model cars) It's because the bulb glass has a tint and that reduces the amount of light that passes through.

__________________
1939 170 - till I was 3, still turns heads
1989 300TE - daily driver has 263k
1987 300E - purrs happily with 120k
1983 300SD - keeps my friend happy