Squadron is a great plastic model outfit, but they don't make or distribute ANYTHING in 1/8 scale,

This guy must be doing the large garden railroad type stuff.

World Models makes an ARF 1/8 cub..not all that scale, but it might suffice:

http://ecsvr.com/abm/shopexd.asp?id=903

I think Global (Hobby People) makes a 48" Cub...that is about 4" smaller than 1/8 scale, but might be close enough for you.