Mario,
Chill dude. There are wheels available. You're going to find all kinds of advice given. Some great, some good, and a lot of it not. If it were me, I'd look at the the tender and, taking into consideration, coupler height and overall appearance (looks too high or low...how's it line up with the loco, etc.) and then decide if you want the exact same height, higher, lower, whatever. Then measure the diameter of the existing wheels and compensate from there.
Drivers are a whole different story and unless you have the ability to machine them or make new ones, I'd talk to Joe. He has absolutely got it dialed in.
Jay
