Thanks to @minions 's data released at Jasmin Leon, I approximated and found the average reward per box at VL bonus stage. The calculated average reward fits my own data. I haven't hit any jackpot (blue VL boots) yet, and from his data, he doesn't seem like have got 6/6 boots or better. Bon: The average reward per box at VL bonus stage is 65m. Taking into account jackpots, that would be 65m - 75m. Belt: At 12-man runs, usually belt looters get 3 belts ea, and bon looters get 3 boxes ea. 18-man runs: 2 belts and 2 boxes. Each godly VL belt is worth 65m × 20 = 1300m (or 1300m to 1400m) Some 18-man runs: 3 belts and 2 boxes. Each godly VL belt is worth 867m to 933m Soul = 500 totems (~400m) + 500m = 900m Every godly 2 att 4 slot belt costs 1.77b to 2.3b VL Chaos Scroll = 500m Each time someone CS'es a godly 2 att 4 slot belt, the cost is: 2.7b to 2.8b (12-man 3 belts/3 boxes, or 18-man 2 belts/2 boxes) or 2.27b to 2.33b (18-man 3 belts/2 boxes) The probability of getting +1 or +2 is 2/5. Every godly 3 or 4 att 3 slot belt costs 5.7b to 7b. Non-godly: "IDC, I just wanna scroll a 4 att 3 slot." 2 att 4 slot belt costs: 65m + 900m = 965m VL chaos scroll = 500m Every non-godly 4 att 3 slot belt costs 7.3b. On average, every (non-godly when clean) 10 att belt costs ~1000b (and hell lots of weeks).
@Sylafia did mention that every box is approx 50m according to her data so your estimate does seem to be aligned with her also.