This includes:
- The default reticle, but made red.
- The gun is replaced with the red reticle when zoomed-in. This will give you the benefit of zoomed in view without the gun blocking what's below it when zoomed-in.

Default reticle - http://i.imgur.com/CcrLu.png - Rename as "target.png"
Zoomed-in reticle - http://i.imgur.com/I711W.png - Rename as "semi.png"

These are made by me, so give credit when linking to them please.

EDIT:
Oh, I forgot to mention I also tested this with great results. To be more specific, I had 13 kills without dying.

http://www.google.co.uk/imgres?imgurl=http://i46.tinypic.com/oucfip.jpg&imgrefurl=http://forums.electronicarts.co.uk/battlefield-bad-company-2-pc/949486-please-reintroduce-optical-sights-g3-m14-49.html&usg=__aR3EGm_GNC4tCw7TI-489__MEK0=&h=577&w=912&sz=33&hl=en&start=0&sig2=xVyYTGdqyAUxFYgRekR-Bw&zoom=1&tbnid=Mcw6vAYenbaR2M:&tbnh=127&tbnw=201&ei=Ng7HTfX2IsWu8QPFxaz2Bw&prev=/search%3Fq%3Dm1%2Bgarand%2Biron%2Bsights%26um%3D1%26hl%3Den%26sa%3DN%26biw%3D1280%26bih%3D933%26tbm%3Disch0%2C200&um=1&itbs=1&iact=hc&vpx=561&vpy=218&dur=3&hovh=178&hovw=282&tx=175&ty=88&page=1&ndsp=26&ved=1t:429,r:13,s:0&biw=1280&bih=933

/\ I think that's in order next? ;)

No.