Susie, I too share your love of old PP black and white photos and I have a number of them framed in my home. Have you been into the bar of the Hotel Daina? There are a number of other pictures there too. Also in restaurant El Posito and a huge picture of the port circa 1910 in Brisa Marina.
When I asked the bar staff at The Daina I was told to find an art shop in the old town of Pollensa that sell old photos. It is called Arxia Bestard. I went there and bought four photos that the shop produced in the exact size I wanted (it took five days from taking the order so do it early in your holiday). They have them all on computer and can reproduce them for you in any size you like. They are, though, quite expensive. For 10" X 8" I think that they cost me 35 Euros each.
The shop is easy to find. Walk into the main square in Pollensa and take the passage to the left of Cafe Espana. Follow this around until you get to the old fountain. The shop is about 25 yds further on the right. You can't miss it because they have a rack outside with black and white postcards of the old photographs.
However, I have since found a cheaper alternative. If you look in the gift shops along the seafront in PP you'll find that many of them sell the black and white postcards of old Peurto Pollensa. I've since bought these and had them professionally scanned at a good photographic shop - total cost less than £5 a time.
I do hope that this helps.