Now I know the best time to dig them up will be during winter... However, can I wait that long... ?

Each of them have good qualities. They all have bark that is starting to split and fissure, GREAT. And I love their autumn colours, what a great tree. For bonsai I think they would make an excellent addition. Great bark, great autumn colours, they produce seed pods, wonderful.
The one with the bent trunk is about 1.2m tall at present, chopped from a good 2m down. Trunk right at base currently about 20cm accross. (pics 05,6,7)
The little one (pic 04), as you can see is just little, but seems very nicely proportioned...
The other, straight up with a fork (pic 03), is currently about 1.2m tall, chopped from about 2.5m, trunk about 15cm accross at the base.