Ive heard that torah umesorah has great resources but I never checked it out. Maybe it would beworth ur while to find out if this is something u can do there
You can upload High res. Jpg to costco they print large posters and ready in an hour. Quality is unbelievable and price is great. $8.99 for a 20" by 30". The best part is satisfaction quaranteed.
I print a lot of my posters there, sometimes I have had an issue where they were not getting the right colors. I bring my sd card and the attendant helps me out right there. (I dont remember if they want the image in rgb or cmyk. - you can call customer service to help as well)
