Identify a short story involving art thieves given a device which can significantly slow time

Question

I read this short story during the late 1980s to early 1990s in an english language collection.

This story involved an art thief asked by some mysterious clients to acquire a priceless piece of art that was on display in a high security art gallery. When the thief suggests it is impossible, he is given a device which significantly slows down time, allowing him to walk in and take the picture off of the wall in the middle of the day.

The story ends with the art thief handing over the artwork to his clients, and asking if he can keep the device. The clients humorously explain that he can keep the device for the rest of his life, explaining that they are aliens collecting significant human works of art so as to preserve them from the impending human apocalypse.

When he asks when the apocalypse will occur, the aliens tell him "moments away in real time", leaving him the option of living out the rest of his life in slowed down time alone.

Answer 1

"All the Time in the World", a short story by Arthur C. Clarke, first published in Startling Stories, July 1952, available at the Internet Archive. Does any of these covers look familiar?

Excerpt:

"You can call this a personal generator," she said. "With it strapped about your arm, you are invincible. You can come and go without hindrance — you can steal everything on that list and bring it to me before one of the guards in the Museum has blinked an eyelid. When you have finished, you can be miles away before you switch off the field and step back into the normal world.

"Now listen carefully, and do exactly what I say. The field has a radius of about seven feet, so you must keep at least that distance from any other person. Secondly, you must not switch it off again until you have completed your task and I have given you your payment. This is most important. Now, the plan I have worked out is this. . . ."

The ending:

Alone! Ashton held the gleaming bracelet before his eyes, hypnotized by its intricate workmanship and by the powers it concealed. He had made a bargain, and he must keep it. He could live out the full span of his life — at the cost of an isolation no other man had ever known. If he switched off the field, the last seconds of history would tick inexorably away.

Seconds? Indeed, there was less time than that. For he knew that the bomb must already have exploded.

He sat down on the edge of the pavement and began to think. There was no need to panic; he must take things calmly, without hysteria. After all, he had plenty of time.

All the time in the world.