The lighter one looks like Philipine mahogany otherwise know as Lauan, commonly used in joinery & windows, It varies considerably in colour & hardness. The sill section is almost certainly Meranti, a closely related species that is harder & heavier.
Funny enough I was just thinking that. Make up half a dozen "kits" based on one I think I posted here. A good solid bench takes up a phenomenal amount of wood.
The other idea is to make a big chunky anvil stand.