Floor covering options? (Cheap)

[68SWB4x4]

Wondering if anyone have any ideas to cover the floorboards while driving and working on the truck before rust repair, etc is finished and I get to the stage of laying insulation and carpet down?

I remember months back at a junkyard I saw a big rubber mat that was like a universal 1 piece floor mat that covered the front of the cab but can’t seem to find anything like it online other than the replacement rubber mats sold on LMc, etc

Thanks for any advice