I think i have got my final design done for my CP art, just gone for a simple background of an abstract high def wallpaper in the form of some sort of hypernova type thing with stars circling the trackball... origional i know

the cp overlay is about 550mm by 700mm, it took 8 x A4 sheets to print out on my printer to do mockups, so i guess that's A1 size paper i need it printed on (thinking that 2 sheets of A4 is A3, thus 2 sheets of A3 is A2, and 2 sheets of A2 must be A1)
i have never had anything at all printed proffesionaly before, so i dont even know what file type they expect... not sure an .svg file will include the background picture which is a raster immage....
But can anyone suggets a firm around the Nottingham area of england that can print the cp for a reasonable cost??
i want it printed on some media that is thicker than normal A4 inkjet paper, so it wont crinkle or sag into the joystick depressions or around the trackball which will be mounted directly to the plexi as golden tee cp's do, it will be sandwiched between 12mm mdf and 6mm clear lexan'
and i want it to be semi glossy, not too shiney and photograph like, but not flat, as on the monitor it looks great with the glowing neon outlines and the glowing red and green stars and that lot,
obviousely when printed onto normal plain paper it looks lifeless and a bit naff.
What do i ask for it to be printed on? i'm thinking the stuff used for wall posters???
basicaly the only place i know that does printing is office world, but i dont think they do high quality stuff... but then again i have no idea.