below are either easy to get, cheap or both.
SoO gear when fully gemmed (costly if u dont have the gems) and correct bonus has around +3 mainstat over a lvl50 nethershard slot but has slightly less secondary stats. any lvl50 legion gear with a socket beats SoO gear.
ALSO, any LFR legion gear is lvl50 so it can be enchanted with old and good enchants. you can target farm ur bis stats in legion LFR.
my sugestions below
head
unless ur a crit class that will stack crit as main stat you can have head as azurite piece for main stat power. if ur crit main stat, then consider running siege of ogrimar for meta sockt of crit dmg
neck (in order)
prydaz stats +socket +hidden satyr
archeology neck has 3 sockets, can be enchanted with hidden satyr
boe neck with +5 mainstat below lvl60 for hidden satyr
legion crafted neck socket and hidden satyr
azurite neck (cannot get hidden satyr)
shoulders
lvl50 nethershard shoulders and +5 mainstat enchant
cloack
any lvl48-lvl50 cloack is enough, either legion crafted or nethershard slot, this way u can get a +6 mainstat enchant
chest
azurite and +30 mainstat SL enchant
wrist
class hall wrists, its from vendor, has a socket, its llvl50 and can get +5mainstat enchant, cant get better than this for wrists
hands
SoO mythic, legion crafted lvl50 gloves, nethershard - can get +6 agi or +8 str or +6str(SL) or +4 spellpower
belt
SoO mythic or nethershards - if u really want a socket (the rest of the gear already covers alot of sockets for the +6 +6 +7 gems) else it can be any belt
legs
SoO mythic, nethershards - can get +5 mainstat enchat
feet
nethershards, lvl48 legion crafted - i dont put SoO here because the feet socket bonus is not mainstat like other pieces. can get +10% run speed enchant or SL agility. the speed enchants beats any other enchant in my opinion. sigryn and twins benefict greatly from this.
rings
SL or BFA crafted greens with ur bis stats - these have an socket you can use for the +6/+6/+7 gems. with wrists/neck u get all 3 sockets filled
trinkets - oh boy
- mechanical dragonling - use a relic5 so it will be lvl54, you can get +24 haste, +24 crit, +12 versa and/or +12 mastery cogs. trinket costs 14 bars to make, each cog costs 2 bars. total of 20 bars and some cloth
- seed pod from first boss in emerald nightare is lvl50 even on LFR more so thats 4 chances per week. amazing vs anything with adds and sigryn
- gaze of sethe from HFC iskar boss - good dmg, strongly advise this and seed pod for sygrin triple cleave, i even used them for Ret pala and Enh shaman sygrin, so much dmg
- dragonspine trophy from TBC gruul is great for arms warrior
- mechagon trinket with cyclotronic blast red card, so much nuke dmg