Dainty Bess does come in a climbing form but it is happiest where the weather is warm. The size of the pot is okay but In your zone make sure you protect it well in the winter so it won't suffer too much dieback.

I am not aware of Dainty Bess as a climber. You can check with the Nurseries listed at this site.
Yes, It can be planted in a container. I currently have started 2 Dainty Bess in 2gal. pots that are starting to bloom. They will be transplant to 20" plastic containers next winter. A 20" container is optimal for roses. The advantages of container planting are: weed control, fertilization, and better soil condition. Also the ease of moving a plant to another location if it doesn't work out in the original location. Search this site for container planting for more info.