and they seem to skip right over 3". Shorter sets such as 1-1/2 inch and 2-1/2 inch are readily available, and actually fairly cheap. 4" is also available, but for some odd reason, I did not see anything at 3". Not even Rockler had a set.

There is a pantograph system available... that might work. Might go that route anyway... you can make some cool stuff with that setup.

I actually found a forum on the web where some guy was asking "why no 3 inch letter sets" and stated he wanted to do USCG documentation numbers... how ironic.

Apparently Craftsman used to make one, but no more.