Try "Tally Ho" in Miami Lakes near KMIA I believe they ship anywhere
Otherwise the OLYMP shirts which are very good quality can be bought on line thoughout the EU (the pilot shop at Eglebach and Cannes stock them) although the wing bars are not a european thing
for my money Landerwood are the very best shirts available and have a great fit
I think some of the USA uniform shops will ship them.
Good Luck