Sifting for pine pellet litter

Hi! I recently switched to a stainless steel litterbox and pine pellet litter. I had previously used clay litter but it tracked way too much and was too dusty. The pine pellet is much better. However, I realized that the sawdust is from the pellets dissolving after my cat urinates and I don't have a sifting litterbox. I'm reluctant to buy a whole new litterbox after I just got the stainless steel. How do you use pine pellet litter and sift the dust? Thank you!