Suitsupply starts with their S (short) sizes from 48 till 60.
Good to know it that the shorts sizes are actually a bit larger than the normal sizes (so a 48S is the almost the same size as a 50 but than shorter).
The Havana model is quiet fitted and a little shorter, I actually like this fit very much (It does have patch pockets, might be too informal, but that depends on the job).
You should probably avoid the Washington which is quiet long and fitted (with peak lapels).
The most formal models are: The London, Lazio, Napoli.
The trousers probably need shortening, however, this often only takes a day.
I hope this helps and good luck on you new job.
P.S. You should probably avoid the Sevilla model. This model is a bit cheaper but the make of the suit is not really good.