I guess you're not listed Cocci.......... otherwise you'd have no choice!
I've never come across hybrid timber/aluminium.
Regular alum units usually come in powder-coated paint finish, in a variety of colours. Can look really good against an old building. No further painting needed.
Timber's ok in strong sun if it's stained (lots of colours available including white.
If painted, then microporous paint is best (breathable). Otherwise, even best quality paints blister and crack in strong sunshine.
If you want to treat yourself ........... hardwood windows, unstained. Many joiners are using "Idigbo", an African hardwood, looks a lot like oak but a fraction of the price.
Also, I assume they are non-standard sizes, so off-the-shelf units can't be used anyway. They'd have to be made.