Olivetti Lettera 35 what type or size of ribbon it uses?

Hi everyone,
I thinking on buying an Olivetti Lettera 35
Does anyone know what type or size of ribbon it uses? Would a universal ½-inch (13 mm) typewriter ribbon work?
Also, if anyone knows a reliable place to buy one (preferably that ships to Peru or internationally), I’d really appreciate your advice.
Thanks in advance!