Use a solid core door from home depot, or lowes for the top.
http://www.homedepot.com/h_d1/N-25ecodZ5yc1vZ12l2/R-100037604/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=sokid%20core%20door&storeId=10051
Buy a solid core wood door from home depot. Best top for the money.
http://www.homedepot.com/h_d1/N-5yc1v/R-100064572/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053