With how small the amount of material is that you're cutting, the blade is almost inconsequential. I say almost because you should focus on two things that will keep your blade lasting longer: get a blade with no set to the teeth or very little set and stone it straight, make sure the blade has more than 4 tpi.
If you're only using it for toneboards I recommend getting the absolute cheapest blade you can find that fits these parameters as it can be sharpened quite easily with a dremel... though the minimal set will keep it sharp for quite awhile since the teeth won't be biting the jig.