They are pin compatible and the EPROM has a slightly faster access time so it should work as a replacement.
Yes, it is UV erasable, the quartz window is to let light through to the silicon, after programming it is advisable to place a label over it to keep light out. I'm not sure what wavelength the curing light is or whether it will be powerful enough. I use 8W tubes at a distance of about 20mm and they take about 15 minutes to fully erase. Make sure the window is clean, old label glue or similar will cause a shadow on the silicon and it will not fully erase. I'm not familiar with your programming hardware but you should find an "erased check" facility somewhere to check it is really empty. Note that an empty device reads back as having all bits set, in other words 0xFF in all locations.
Almost all EPROMs of the same size will program in identical fashion, the major difference is the voltage you have to apply to put them in programming mode. For the AM27C256 series it has to be 12.75V +/- 0.25V on the VPP pin and 5V on VDD. Other than that you can probably program it with any '256' EPROM type selected.
Brian.