[Leica] Improving IIIf r/f contrast -- cheapskate version?

[Stephen Alred <salred@toad.net>]

All,

My IIIf black dial is usable in sunlight, but inside the rangefinder just
about disappears. As I understand it, I have two options to help my focussing:

1) Repair the beam splitter in the r/f mechanism -- for this I have a $195
quote from the folks at Photography on Bald Mountain (baldmtn@pacbell.net
for those who might be interested; and
2) An orange filter for the r/f window -- seems to be definitely a
collectible, since by bid for one on eBay was woefully inadequate!

So:
a) Can anyone vouch that the orange filter actually improves things, and
b) If so, can someone suggest a CC filter equivalent -- I'm not too proud
to fabricate something...

Thanks

Steve Alred