Inductors with no value on schematic
I think that you can safely assume that the inductor symbols are indeed ferrite beads.  I base that on the filled rectangular block used for inductor L2.

R18 is an adjustable resistor (potentiometer).  The arrow indicates the clockwise direction.  That is: the wiper moves Down as the shaft is turned clockwise.  Note that this could be a front-panel adjustment or a trim pot on the PC board - there isn't enough information to tell.

I can't offer an opinion on which ferrite bead you might use but I frequently use Digikey part # 240-2563-1-ND - this is a Laird-Signal Integrity Products  LF0805A252R-10 FERRITE CHIP 2500 Ohm, 100 Ma in a 0805 package.  If I recall correctly, DC resistance is significantly less than 1 Ohm.