Going by ragial's avg prices for stuff that gives descent results:
+7 Pororoca Shoes - 240m (+0 would be ~70m)
+0 Temporal Dex Boots (clean) - 5m
+7 La'Cryma Stick - 5m
Nightmare Ancient Mummy - 300m
+9 Spell 667 FAW - 800m
+0~9 Ordinary Black Magician Hat - 50m~90m
2x Alchemy Glove - lul
Red Lichtern Card - 8m
Big Ben Card - 180m
Neo Punk Card - 250m
Nightmare Arclouze Card - 200m
Nightmare Mimic Card - 120m
You can also try to farm the cards yourself, or wait for an enriched Hammer event to upgrade the gears on your own.
There also is no need for a max Spell FAW, you can settle for (slightly) lower values. The FAW's refine level combined with Nightmare Ancient Mummy Card is what brings the big numbers.
Then for leveling until 150 you can technically ignore Nightmare Arclouze, Nightmare Mimic, Big Ben and Neo Punk Cards and just default La'Cryma + Pororoca.
You can just farm those cards once you are 150 or buy them when you have more founds.
Which is why I left those 750m is a second calculation. :v
Comparing to GX:
+7~9 Immune HBP - 250~390m
+9 Rideword Hat - 300m
+7 Malicious Thanatos Katar - 90m
+0 Temp Str Boots (clean) - 10m
2x Rogue's Treasure - 2x 135m
~1b and ~1.35b is not really too big of a difference if we're being honest.
And both lists are pretty much what I'd consider basic gears.