Asking for a colleague whose rear Drums are knackered 5 x 112 pattern,

Think this might be a bit of a wild goose chase, it turns out the drums my mate has have been redrilled to 5x112, so not entirely sure what he has on the rear

that is a VW water cooled wheel pattern

55 drums can't be drilled for that pattern, are you sure he hasn't got later ones fitted? Could you post a pic?

Having seen pics of his drums, it looks like whoever built this buggy bodged the brake drums with some very dodgy welding, so I think the plan now is to replace the whole rear brakes with a more appropriate setup.

If you swap the whole rear brake setup for post 68 ones, you can get blank drums for them (Machine 7 etc) to drill for any patterns, if you've still got early short axle shafts you'll need 14mm machined of the drums 'snout'.