I have a friend that has an Ostrich 360 Sprint car motor for sale for 15K. Can probably be had for a touch less. Dynoed at 650 I believe, ready to run. You can search racingjunk.com or hoseheads.com and find plenty of what you are looking for. Keep in mind that all the high reving motors have to use good quality parts to keep them together and even then, they get freshened up after about 20 shows. Word of caution, unless you have lots of money for parts, stay away from the SBC 410 sprint motors. Those things will scream and capable of 900+hp but they are very costly to maintain and need freshened after about 10 shows. Most sprint car motors are built with restrictions for their sanctioning body so with a little work, you can get even more power out of them.
We run a SBC 383 Hilborn Injected on alcohol in our wingless sprint. We run the W.A.R. series here in Missouri so restrictions in that class do not apply. It's more like "run what you brung". Alcohol wants high compression, the more the better. Keep in mind that an alcohol motor is a maintenance nighmare but if you have time to keep it in good working condition, it's worth it because of the x-tra HP. You need to drain the fuel lines, remove the injectors and blow dry all the alcohol out of the system. Alcohol is very corrosive on aluminum and magnesium parts.
I know probably none of this answered your questions but it's an insight to start with.