Since it's no longer the best, here's my 7 Colonies solution:
Kingdom: Poor House, Secret Chamber, Squire, Stonemason (Bane), Scrying Pool, Hermit, Market Square, Storeroom, Black Market (Black Market deck includes Baker, Death Cart, Young Witch), Remake, Festival
Play Copper, buy Poor House
Buy 30 Ruins
Play Poor House with no treasures, buy Stonemason, overpay 2, gain Squire, Secret Chamber
Play Secret Chamber, discard hand, buy Remake
Play Remake, trash Estate, gain Hermit, trash Estate, gain Market Square
Play Hermit, gain Storeroom, trash Estate, discard Market Square, gain Gold, trash Hermit, gain Madman
Play Stonemason, trash Gold, gain Potion, gain Festival
Play Abandoned Mine, Potion, use coin token from Baker, buy Scrying Pool
Buy all but 1 Copper and Curse (from now on "c" means one of these)
Megaturn: starting hand is cccc+Scrying Pool
Play Scrying Pool, draw 30 Ruins, Poor House, Remake, Secret Chamber, Market Square, Stonemason, Madman, Scrying Pool, Squire, Storeroom, Festival, copper/curse
Play Madman, draw 44 copper/curse -> 1 buy 2 actions 0 money
Play Festival -> 2 buys 3 actions 2 money
Play Squire -> 4 buys 2 actions 3 money
Play Market Square -> 5 buys 2 actions 3 money, draw copper/curse
Play Ruined Market -> 6 buys 1 action 3 money
Play Storeroom, discarding 29 ruins, 50 copper/curse, Poor House, Remake, Stonemason, Secret Chamber -> 7 buys 0 actions 86 money
Buy 7 Colonies