Just had a look at Slaters and Squires lettering, I guess the same thing.
For 1/48, 3mm seems the closest, had a quick count and I think it could be done with three packs.
Applying them could be straight forward, if a little fiddly.
Mark the vertical spacing onto a strip of masking tape, stick tape vertically into position on the hull, and starting at the top mark, put a horizontal piece. apply letters along the horizontal tape, move tape down one space etc etc.
Gluing, possibly a spread of super glue on plastic and a pair of tweezers, fiddly but feasible. (I think)
Colin