lvl 9 you have two options:
3 shout 3 sock
3 shout 3 mastery (mace/sword/axe) 2 socket
bash can spawn, but it operates in the same fashion as holy shield, whirlwind etc where it isn't supposed to spawn in game due to the (rather odd) coding that was implemented in 1.10. but if the game rolls an invalid staffmod like bash/hs/ww 6 times then the next roll it can spawn and if the game selects an invalid staffmod it will be there for you to use

basically good luck finding a barb helm with it and even then, definitely good luck having it with 3 shout/3 mastery on it because bash, being a T1 affix, will only spawn in parts of normal mode (mainly A1-A2)
ww/hs are much more common being T6/T5 affixes and having the ability to spawn on very high ilvl items, which is where most MFing occurs
lvl 18:
3 conc 3 shout 3 iron skin 3 socket. conc functions similar to bash, but again is unrestricted by ilvl reqs so theyre much more common. shout being a T2 affix complicates matters so, i think this helm is best found in norm cows. 3 shout/3 iron skin can be found in nm/hell whatever so much easier to find and much more common
some detail here:
https://forums.d2jsp.org/topic.php?t=14503106&f=143https://forums.d2jsp.org/topic.php?t=67041534&f=87https://forums.d2jsp.org/topic.php?t=64297647&f=87This post was edited by excellence on Oct 17 2020 10:36pm