I'm going to help you out here and I want to make it perfectly clear: I am not interested in bidding on this job, nor have I ever done bid work on here.
You want a total of three hundred machined parts (100, 100, 50, 50) for $1250? That's an average part price of $4.17, including the material.
If a tooled CNC machine fell out of the sky and landed in your garage, a lightning bolt struck you with instant knowledge and somebody mistakenly mailed you a copy of Mastercam, YOU couldn't make those parts for $4.17 each.
You will probably need to either go to a country where the daily wage is a bowl of gruel or rethink your marketing strategy (target price, complexity of the parts, etc). I realize some of the parts are smaller than others but, I'll bet that you're looking at at least half of your target price in materials and cutters. There are cost-reasons why certain products never make it to market.
Of course, somebody is going to come along, bid low to get this job, make it out of leftovers in their own inventory, then lose money making the parts.