The PT-40 is magnificent, Ilearned on one.
The engine choice is fine, but a better one in my opinion is the Thunder Tiger GP42. It is a bit simpler , durable, powerful, reliable and easy to tune. and in stock now.
And the batteries? You could try your local Harbor Freight for rechargeables cheap.
Here is a really nice radio that comes with a receiver and extras for a few bucks less.
http://www.hobbypeople.net/index.php...tx-fhss-1.html