the gtir ones are different so not really an option, the rads on gtir's are in between the rad support not between the support and the turbo. it is like that coz of how small the engine bay is.
i had a 40mm thick aluminium rad custom made for 700 and it does the best job of keeping the engine cool, so much better than the stocko items on any car. this is probably the max you'd be able to go.
if the U13 rads are the same as the U12 ones the it wont be a problem to get one made up. if they are slightly different then get a shitty messed up rad and take it to a rad place they will tell you where to go to get it done