This race attracted many of the biggest names in mower racing, it could become one of the premier events of the sport. Having the event at any facility will gain that facility notoriety and prestige. Maybe you should talk to the track owner about weighing the pro's and con's of having the race at his facility?
Drivers appreciate racing with insurance, we have no problem paying $5 to cover the cost of insurance.
If the race cost him $1500, he would only need to charge $7 for a couple hundred fans to cover those costs.
COncessions should help as well.
Maybe it would be good PR to forego profits for the event, if his tax man is worth his salt I am sure he could write off most costs.
Sponsorships help greatly.
Just some Ideas for you, but underlying message is "Look for creative answers". The financing should not be an issue.
Charging the drivers that much will hurt the event.
On the drivers side of the equation:
Drivers talk to your sponsors, let them know you think it would be good to attend the event but need some extra help to cover the costs. It is not unusual for sponsors to add a little extra for a special event.
If you do not have a sponsor, consider the costs an investment, good finishes at events like this or even simply attending them help build your "Racing Resume" that make you more attractive to sponsors.
Events Like the National Racing Series, the All American and The V-Twin Shootout help the sport. They bring it more into the public eye in a positive manner. All of us from the single driver, race teams, race promoters, club Officers, track owners to the Heads of the national Organizations need to work together to make events such as these as successful as they can be.