Tried something similar to this with Stalker's/Devourer, Guinsoo's, Gunblade, mercs/swifties with alacrity/furor, then visage with situational armor.
Let me just say, your abilities do a ton of damage and your autos are not useles for once which is great.
For masteries, I went 12/18/0
Ferocity
Tier 1 AS
Tier 2 double edged
Tier 3 lifesteal/spellvamp
Tier 4 preferecne
Cunning
Tier 1 savagery
Tier 2 either assassin or the buff one
Tier 3 preference
Tier 4 DG
Tier 5 pen
Tier 6 thunderlords
I guess you could go 6/18/6 for more tankiness early but it's up to you