I purchased some flags for the model that I am building from a source that you don't normally see advertised, the name is Mike Allsop. "Scale Flags & Ensigns", unfortunately he does not appear to have a website but I have met him at several shows. He has a vast amount of knowledge, and books on site, so you can go through them with him and get exactly what you require,at the correct scale; these are printed both sides on silk so give an excellent representation of the full sized flag.
I do have his phone number and home address on his business card but will not post it on line, if you would like it please send me a PM and I will email it back to you.