Sorry I've left it so long, I've been pondering...
And all this could be in vain if you have already gone down this road, but here goes,
O.K. your dead right about it being an expensive prototype, even making the casings from ally plate, bolted or welded together to save further money.
I'm guessing the manufacture and finishing of the internals and purchasing the hydraulic control unit are going to be the most expensive?
Then there's dyno time.
How small can you actually make the rollers and still get a valid proof of concept?
Is it possible to at least get the diameters of the largest discs down to around a foot or less so that they can be produced on the most commonly available machines or would this wreck everything?
Whats the comonality of parts like? Can the 3 discs be made to the exact same drawing? and the rollers the same? that would save big in the short and long term.
Do you know companies that could tender for this work in your area?
It's only a quote after all...
I know a bunch over here but could forsee three problems.
1.Getting specialist steel yourself in small quantities is going to be difficult (unless you know someone who orders it in larger quantities), getting a contract machine shop to supply that steel is probably just as hard, especially finding one that can both supply the steel and do the work. Can it be made from more commom grade? even with reduced service life on the prototype? I'm sure those steels are widely used but i'm talking one of the top two or three types of steel likely to be used by machine shops in your area who carry out this sort of work. Talk to them.
2. Even placing orders on behalf of an established customer I used to get moaned at by sub-contract machine shops when placing orders for very small batches with new tooling requirements, they would often load the price pretty high so as to let us know they didn't really want the hassle. Being a regular customer you can sometimes strong arm them (in a polite way) into doing it for less, but coming from nowhere this would be difficult. They are much happier making 30 than 3.
3. Contract Heat treaters will charge a fee per oven regardless of how many items so as many parts as possible need to have the same treatment and it should hopefully be something not too obscure so it dosen't need a custom program.
Finally I would be adding 1 off or even 2 off spares per part/order because right first time isn't always in these folks vocabulary, and I'd have someone with excellent inspection/Q.C. skills to check the parts when they arrive in case they need to be rejected back on the supplier for non-conformance.
Also the age old issue, you don't have any parts which could be made significantly cheaper by splitting into assemblies do you? no deep blind holes with very tight tolerances etc.
I know this is probably just wasted gas on my part, but if not, getting quotes is free and it would be the next stage of development. It's more credible to approach someone for funding if you have recent quotes.
Also all these problems are from a U.K. point of view (and i'm out of it for a few years now, things might have changed but I doubt it will be that different) I know the U.S. has a better range of raw materials available. Having said that the machine shops over here are very good. I've heard it said that Japanese motorsport companies are sometimes forced to have their more complex rapid manufacturing done over here because nowhere else in the world can go from drawing to turning out finished product so quickly & cheaply with so many sub-contract processes.
N.B. Before Anyone gets hold of this and cries outrage, The Japs and the Germans tend to get a higher number of parts in the batch right. I.e. their quality records are near perfect and the U.K. can sometimes struggle, (although this seems to be on an upward swing at present) so they still have reputations to be proud of and produce some of the best kit.