Altiris administrators can see the total size of the Patch Management Bulletins, however the individual package sizes are not displayed in the console nor is there a report that shows the size.
The following SQL will list the individual package size per Bulletin Name:
select sb.[Name] as [Software Bulletin], su.[FileName] as [Software Update], su.PatchSize, su.ReleaseDate
from Inv_Software_Update su
join ResourceAssociation as ra
on su._ResourceGuid = ra.ChildResourceGuid
join RM_ResourceSoftware_Bulletin as sb
on sb.[Guid] = ra.ParentResourceGuid
where sb.[Name] like '%BULLETIN NAME%'
order by sb.[Name]