Yes. The height of the letters will be determined by the height of the plaque. So, Standard will have 1.25" H, Large 1.5" and Estate 2" H.
If you want taller letters, the small address plaques section will have more:
http://www.ourcornermarket.com/Small-Address-Plaques.html
Here's one that holds up to five 3" characters.
http://www.ourcornermarket.com/Cambridge-Address-Plaque-Small.html
And here's one that holds 5" numbers:
http://www.ourcornermarket.com/Dresden-Address-Plaque-1-Line-5-Numbers.html