I got this nice crane on ebay last week, new £15 and free postage.
It looks good and lots of movements.
It is about 10 inches tall and i think it's good for that price.
Sometimes you have to just throw it on and see what happens.
If it turns out ok then leave it.
That looks better but i would use more brown, it's up to you.
If your happy i'm happy.
Plenty of examples on that web link.
It can be hard to judge the colours on a computer but look at the pic's on the web and try some.
The only person you have to please is you.
Here is a picture that shows all the colours in a stone wall that should be close to what you want.
study it closely, the more you look the more you see. good luck, you have a lot to do.