What wood to use to replace missing floor boards

[ScottishGasMan]

Hey all, at some point while renovating my house I've skipped floor boards that were to go back down, they are about 27mm thick old old boards, forgot to measure width but at a guess 4 inch approx,

Looking to see if 27mm is a size you could still get or what's the easiest way to replace missing sections? Aesthetics doesn't matter as there's decent underlay going over with reasonably thick laminate/realwood flooring after

 

[Deleted member 174758]

27mm isn't often available so go for the nearest thickness you can get and install it using thin plywood or hardboard packers on top of the joists to bring them up to the same level as the existing boards. Builders merchants also sell packs of graduated plastic packers in mixed bags (1, 2, 3, 5, 6 and 10mm commonly) which can be used instead