Since your printing on wood and it needs a receptor precoat before printing you could use the Inkaid white matte precoat.
2 or 3 coats will not completely cover the grain but your wood will have a white washed finish. At least you have a little more of a white base to print on rather then the natural wood color.
When I sold my cabinetry business I kept my 3 large veneer sample books. Approximately 125 veneer samples from around the world.
So lots of really neat grain patterns to play with. They are raw veneer with no backers and measure at around .020, Perfect for my 3800.