Or you just buy and install the newly designed parts from the 2014 model.
Lower filter case: 60306001100 euro 25.68
Screws: 0017060305 euro 1.47
Air filter frame:60306016100 euro 10.07
O-rings: 0770066025 euro 3.53
Total cost in parts: euro 40.75
Given that a 2014 model costs about 1000 euros more compared to the 2013, I signed the order form for a 2013 R and will sort out the airbox myself, either with the Uni filter or by retrofitting the new KTM parts.
2013 KTM 1190 Adventure R
1988 BMW k100RS sidecar hack
1989 wrecked BMW K100RS (currently being café racerised)