I have 2 buddies that are lefties...and we all shoot Wilson Combat 1911's.../ an Ambi safety is a good option for lefties and Wilson combat has a number of different options for the safety for lefties ---bigger, wider, etc....
Wilson also offers a recessed slide lock pin ...so it makes it less likely to be bumped by the grip of a leftie....
both good options...
A new CQB ...or a Protector model ...( in 5" guns ) will cost you around $ 3,600 depending on the options you pick ( mag well, sights, finish, etc ).../ the lead time on a new order is still about 18 months.../ but there are a number of Wilsons for sale on Gun Broker from reputable dealers that have orders placed out far enough to be getting some inventory ...both in 9mm and .45 acp...( personally I like both calibers in a full sized, all steel 1911 - with a speed chute or mag well, ambi safety, recessed slide lock pin, rear battle sight, front fibre optic sight in green, Armor Tuff finish or all stainless...)...