I suspected it from the beginning but did not want to say anything until I saw the stamp. As the number three is in the text below the immigration officer's signature, it is definitely the number of the immigration office or immigration division to which the officer who collected the fine is attached.

You are not blacklisted and are free to travel to Thailand at any time.

In future, better not overstay as tougher rules will come into effect starting 20 March 2016: http://www.thaivisa.com/forum/index.php?app=core&module=attach&section=attach&attach_id=360548

Well, that was worth waiting up for. I'm off to bed. Nighty Night

I apologize for my negativity Peter hearth. I thought you were a troll, but it appears not so.

Good to see you have your answer and it is favorable to you.

I love a happy ending

I happen to know the op and he is a genuine fella who for his own reasons overstayed. We could all get ourselves in a pickle and I hope people can be helpful to you, if the need arises. Thanks for those who have been reassuring, as he mentioned, he has a wife.

Good luck, I return after days with this stamp. The only difference on mine is longer overstay days. So don't worry can come back, just make sure you have the money 10k for visa exampt and 20k for single entry and some hotel booking. Best to have a return ticket. I have it all when I return just to be safe but they did not ask for it