Curtis at latheinserts.com used to work for Kennametal and now sells stuff on his own. He can give you good advice on what will work, particularly insert setups for those of us with smaller lathes. He frequents practicalmachinist.com. You can find him by his handle ExKenna.
He has dead sharp polished inserts for aluminum that work really well. They work so well, in fact, that I need to get a stronger toolholder. I can part aluminum without using backgear, but it trashed my first toolholder.
You can reach him at Curtis at latheinserts dot com (do the usual replacements).
There is also AW Warner, who sells inserts made of HSS that fit into standard toolholders. Nice thing is that resharpening is just laying it face down on an oilstone and rubbing it. You can get Warner inserts from littlemachineshop.com.