Motorized wheels for paper BART model train?

[homersimpsonlikestrains]

I am planning on building an N scale BART train layout, and I found this site that produces paper models of BART trains:

Wurlington Press BART Train

Does anybody know where I can get powered wheels that I can place underneath the paper model BART train?

 

[dgrafix]

I know greenmax do several sizes of bare motorised chassis in N 17/18/19/20/21 meter scale.

Greenmax (Power Unit) Products List - HobbySearch Model Train N Store

Hobby Search sells Greenmax (Power Unit) Model Train N on-line, fast and secure. We are a mail-order retailer carrying a wide selection of Model Train N in stock.We provide latest information on pre-order items through e-mail newsletters.

www.1999.co.jp

You can buy this on many stores around the world.

I have also seen single motorised bogie units, but don't know who makes them, maybe Kato, Tomix or even these people. You could also look at any spare part where the bogie+ motor is self contained and not on a drive shaft.

 

[dgrafix]

PS: 5000yen is about $35, plus whatever your import vat is.

I was going to buy one of these (perhaps the 17 or 18M one) to try and 3D print an Intercity 125 but am not sure of the IC125 wheelbase. It's hard to get a decent measurements diagram of the real train to see if one will pass.