Or make your own - layout LEDs in series, say 5 in a column driven from 12V and a 7406 (open collector output good for 30V), or 2 columns of 5, per digit.
Write out to a shift register to turn the segments on. (clock & data signal).
tpic6b595 open drain shift register, this combines both features. Go to 24V put 10 LEDs in series per segment.
Can make as tall as you want!
I also saw that vellemanusa.com has a big digits, not sure how tall. Look in their kits section.