Based solely on looks the Stinson Reliant is probably the closest plane you have to work with. I don't remember if it is original to the program or from one of the add-ons. Use the Cub if necessary.
Just go to the "aircraft" pull down. Chose which ever plane you decide to start with and click on "make a copy". Name it whatever you want. Now go into the edit area and input every measurement you can from your plane. Almost every parameter will have a "help" question mark by it and will tell you what it's all about. Don't forget......every measurement! Even then you'll probably have to do some fine tuning especially where speed is concerned. It's usually way too fast compared to the real thing. I usually go to the fuselage section and start adjusting the frontal area to cause extra drag. It works well for me.
It's really not that hard to do. It just takes time and a bunch of measuring tools if you want it even close. Give it a try it's actually a lot of fun.