1. I suggest you consider what your anticipated amortization schedule would be for the cage - that's what helped me relax about the cost involved.
$4000 cage / 10 races = $400 / race
$400 / race // 4 drivers = $100 / driver race
That's not too much
2. I would be surprised if any cage builder gave away measurements for any reason.
There's work and expertise involved in taking measurements for yourself; that's your intellectual property.
Any perceived poor, incorrect, or misunderstood measurements could diminish a reputation; I wouldn't do it for you.
Besides, you can measure it yourself, and get the kit exactly the way you want it.
S&W Performance Group (swracecars.com, 12 miles from me now in SE PA; not particularly useful for you because shipping) lists kits for certain cars which use _their_ measurements; that is: their engineer measured the cars which came in, and the tubing is bent to those measurements.
Those measurements are primarily for cars with the interior still intact; that's what they say on their website. Also, there's a lot of local drag strips, and there seems to be a showroom stock group(?) that's pretty active, which explains the corporate focus.
This might also explain the comments that 'kits take too much room' - guessing they're designed for the more prevalent 'intact interior' cars, not stripped race cars.
I also stopped in and got to talk to the (owner? manager?) answer guy, because I have a Lemons candidate with relatively low production numbers - SC400.
He said I could bring in a stripped car, and his engineer would measure it, and they would design and bend a kit specific for that car with the interior out. He seemed interested in me doing that, because they didn't have a stripped SC400 in their database.
Or, that _I_ could measure, and they'd bend a kit to my specs.
In the 'Lemons Roll Cage' item, there's a link to a data sheet which includes a 'tubing bend template' to facilitate measurements for them.
For them, a kit with 1 3/4" x .120" DOM Lemons cage ~$808, and NASCAR door bar kit for $170; EWS: ~$485, then the NASCAR door bars. Plus shipping, of course.
I could also arrange for them to weld in a cage if I left the car there. It was two years ago, but I think he recommended the seat be installed so the cage could be measured.
Wouldn't surprise me if any good supplier would offer the same service.
RCC gets a lot of recommendations in this forum.