I'm not for Guam, nor for a heavy wind speed area, but this is the question that is too general to obtain a direct answer.
What is the span, the loads, the roof pitch?
All of this will define the Section Size, which depends also from the spacing. You can create some spreadsheet, or find one, and test, for your particular case, which combination of spacing and section size is more economical. The limit spacing will depend on the maximum distance that the roof can Span.
If your question is more related to availability of secrion sizes, then contact the local companies.