I'm nearsighted and I don't have problems with 13.3" notebook displays. In fact, I find 12.1" and 12.5" fine as well. You can adjust font sizes in Windows and in individual apps if necessary to make text larger.
There are several thin and lights on the market these days that don't cost an arm and a leg. These are all around $1,000 or under:
Toshiba Portege R835 (the update to the R705 we reviewed and liked quite well) Sony Vaio S series Lenovo ThinkPad X220 (depending on config might run over a grand but they do have coupons and deals). This is the highest end of the bunch. Lenovo ThinkPad Edge 420s- it's a 14" that we'll be posting a review of soon, but it's extremely light and thin for a 14" machine... around 4 lbs.
-------------------- Lisa Gade Editor in Chief, MobileTechReview