Interior rain seal question
I make my own plastic shields from clear plastic, use fairly heavy gauge material. Last set I made were from left over shipping plastic from some mattresses we bought. Stuff was nice and heavy. Use your door trim panels as a guide, trace around them on the plastic, then cut about 1/2" smaller than the outline. Check the new pieces against the door itself as a reality check.
I like using spray adhesive, which you can buy at the hardware, duro brand or whatever. It does not really have to be a permanent bond, you can get away with just about anything as long as it sticks until you get the door panels installed. Do tuck the bottom edge inside the door as recommended above.
Have at it !