Hungarian Porto overprints - postage due stamps

there are a number of types:

• Overprint "P"
• Overprint "P" in circle
• Overprint "T"
• Overprint "Porto"
• Overprint "Porto" in oval
• Overprint "Porto" in rectangle
• Overprint "Porto" in circle
• Overprint "number" in circle
• and all with different ypes of fonts

Here are some examples from my collection.