Our runway is going to be repaved next month. Its 550X42ft and the quotes have come in around $20K.
The original runway is about 1inch thick which is too thin. The cold snowy winters have caused huge cracks in it which have been filled and maintained over the years. This has been very costly for the club.
The new black top will almost double the thickness and make it nice and smooth. Be sure to order the thickness at least 2-3in so it will last through heavy winters and so you don't have to pay for it again later on.

Also if you tell the local asphalt guy they can have a sign to advertise at the field you might get a little discount, call them a sponsor. If they need a write off they will get a tax credit if your a nonprofit org.