Piece of wood - old shelf say (Elvington CT15)

Seeking one or two pieces of wood approx 300mm x 1m. Hoping someone has some spare laying around. Length doesn’t matter as long as not less than 850mm. Width minimum 250mm max 300mm and thickness of at least 15mm
Something like pine board pictured would be ideal or any solid wood but actually can be anything apart from chipboard eg MDF works ok if need be . Doesn’t have to be pretty. Can be marked or painted or some holes and still works for my purposes. Anything that’s dry having been kept indoors and has a little strength in it. Not palletwood thanks.