I would look for a later software version (or latest SW, like Carolpa’s) if I was looking for a BS3000, rather than worrying about clamper size. Obviously the earlier ‘small clamper’ versions are more likely to have earlier software, unless they have been updated.
If you search BS3000 on UK eBay they often show photos of the labels so you can get a good idea of Type Numbers, SW versions and clamper size.