Where to buy a bigger crankset

Hello everyone!
I have this Csepel Royal 3 fixed/ single speed bike as you can see, and i want to buy a bigger crankset. I have already changed the original 42T crank to a 48T, and i have a 17T on the rear.
My problem is that i would like to buy a bigger crank (60T or slightly bigger) that would fit my bike, but i couldn't find any website in the EU.
My current cranke is a Csepel Teta 48T (red painted), 1/8'' profile with a 130 bcd, with 5 screw fastening.

Thank you for your time and help.
Have a nice day and a safe ride!