Sorry for thread necromancy, but I wanted to add this in case anybody comes across this thread:

I ended up having my poster map printed from a local photo shop. Ended up paying 20 Euro or so and it took them 4-5 working days. I first ordered a smaller (cheaper) sample, which was glossy. For the bigger poster I went for a matte print, which was a good choice. I uploaded sample photos (of low quality) to my blog and to other threads.