You may be able to buy it off ebay. But probably not.
They should stand up fine. You just need to balance them properly.
You could make your own stand.
You could get something of your choice to be the base then get some thick wire (small enough to fit in the holes in the bottom of the figures foot) and somehow stick the wire strongly into the base. Therefore resulting in a cruedly made base.
I wouldn't say it is necessary though.
The figures should be able to stand by themselves easily enough, providing that you aren't constantly bumping the shelf or table they are on.
