So a bit more digging around and it looks like the Indesit OS1A200H2.1 might be the good candidate here.
At 865 (H) x 806 (W) x 642 (D) we should have an interior floorplan of approximately 650 (W) and 490 (D). With each keg being 230mm round (allowing for a bit of a gap) there's space enough to comfortably fit 4 kegs and possibly even 5. What's quite good about this freezer is that it can be set as either a chest freezer or a chest fridge.
The only thing I'm not sure about is that there is a light on the inside of the lid, so fitting a collar might be tricky, although I'm sure it wouldn't be too hard to terminate the wires.
At 865 (H) x 806 (W) x 642 (D) we should have an interior floorplan of approximately 650 (W) and 490 (D). With each keg being 230mm round (allowing for a bit of a gap) there's space enough to comfortably fit 4 kegs and possibly even 5. What's quite good about this freezer is that it can be set as either a chest freezer or a chest fridge.
The only thing I'm not sure about is that there is a light on the inside of the lid, so fitting a collar might be tricky, although I'm sure it wouldn't be too hard to terminate the wires.