VBA Create attblocks

Hey folks

i wrote my first cva autocad script today and was wondering if you's could pass on any advice:

the script creates new attdefs that are replicas of old block attributes:

Sub Block_edit()
Dim objCount As Integer
Dim mspaceObj As AcadObject
Dim att As AcadAttributeReference
Dim block As AcadBlockReference
Dim i As Integer
objCount = ActiveDocument.ModelSpace.Count

For i = 0 To objCount - 1
   Set mspaceObj = ThisDrawing.ModelSpace.Item(i)
   If mspaceObj.ObjectName = "AcDbBlockReference" Then
       Set block = mspaceObj
       retval = block.GetAttributes()
        For Each c In retval
           Set att = c
           Set new_att = ThisDrawing.ModelSpace.AddAttribute(att.Height, acAttributeModeNormal, "", att.InsertionPoint, att.TagString, att.TextString)
       Next c
   End If
Next
   
End Sub

It works fine but i don't know how to create a selection set or collection of these items so i can turn them into a block later on.

Any suggestions would be great

Thannks

Ollie.