cheapest and easiest now should probably be the fell oak. the club is the cheapest base item to gamble for of the tc3 uniques, and you have the 1 in 2,000 odds right at lv 1. honestly, this was probably ALWAYS the cheapest and easiest to get. just no one wanted it like they want gull daggers. lol
Lenymo would be cheaper... if you could get it at 1 in 2,000 odds before level 15.
Same with hotspurs, which you need lv 12 to get the 1 in 2,000 odds to gamble.
meanwhile i found the maxroll gamble calc which supports ur suggestions - good answer, thx will tip!
one add: playerlvl 5 has the same costs for gambling felloak at 686 gold as level 1 but transfering gold is way easier
so conclusion:
Lenymo at clvl 15
Hotspurs at clvl 12
Felloak at clvl 5