Help identifying camera?

While "organizing" the chaos known as my photographs, I came across some peculiar negatives from the mid 1960s. The film itself is 120 or 620, but the frame size is 4.25 x 4.5 cm. I've searched extensively and the only camera from that era that I can find that took 4x4 was the Agfa Isoly, and I'm certain we did not have such a camera. To deepen the mystery, I was the person who took the photos, but none of the cameras that I had at my disposal could have taken these pictures. I'm all but certain that the only camera I was using at the time was a Yashica TLR, probably a Yashica-A. I know that Yashica made a 4x4 TLR but that was clearly not the camera that I had, as attested to by the numerous 120 6x6 negatives that I have from that time.

 

Any ideas?

Diana cameras were available in the 60’s. They used 120 film and made an image a little bigger than 4x4cm.

It is a camera easily forgotten.

I knew the Diana made 4x4 images, but I didn't realize they were around in the 60s. According to Wikipedia, they were often given away as novelties. I wonder . . .

There is also the Coronet Rapier.

I had a Bilora Bella DC4 which took 4 x 4 pictures on 120 film:

 

The Bilora Bella DC4 - Warts and All

An actual scan of the full area (including margins) of a negative might help. Some cameras had markers in the edges like the notches on larger format sizes.

STill have a ROlleiflex Baby 4x4 which also takes a little larger than 4x4 , but also a magazin for my SL66 which takes 4.5x4.5 , so maybe you used to have a Rollei SL66 series or a Rolleiflex Baby ?

This isn't your answer, but there is a Japanese folder, the Atom Six, which can make 12 square pictures on a roll, which are rather smaller than normal at about 53mm square, or with an extra mask, makes sixteen frames about 50x43mm on a roll. This is close to an old Japanese plate size, though whether that's why they chose to do it is doubtful.