All you really need is a single hinge and a strut. I've heard that Volvo tailgates, mid 90's Pontiacs, and Ford Explorer lift gates provide good salvage yard struts. For a specific strut contact RV shops in addition to the normal strut mnfrs. You will need to know your compressed and extended lengths as well as the force required, which will be more than the door's weight (especially if you locate the strut at some weird point).
There are a few Lamborghini kit car companies that provide hinges for about $100-150 a piece. If you can get them to sell to you, then you're better off than most people.
Also you need to think about the weight of your door.Fully assembled Lambo doors are about 65lbs or so. If you are converting an existing car, making a fiberglass copy of your doors would help.
these kits too expensive for you?? Think about what will happen once everyone can buy this kit. How cool it will be to have scissor doors when they will be as easy to bolt on as a cold air intake? Once every kid down the block gets scissor doors, this mod will become as cool as euro lights. Everyone likes these doors because they are hard to replicate. That is why they cost so much and also why you won't find a lot of people talking about them. The first people to make these modifications spent a lot of time (and money) working on the designs so they would work the right way. This is why they win trophies and, more importantly, why they deserve a lot of respect.