I assume is this one?
https://www.ebay.co.uk/itm/114826103035?hash=item1abc2b48fb:g:xOAAAOSwucBgmudi
Make him an offer on the spot? For the same cash you can have a nice late oil cooled 1200GS.
Had the 2013/14/16 and 19 models. First one dumped all the oil from the little hole by the left side rocker cover, sometimes there is green marking around that hole, cooling escaping. Could be that the pump is kaput but some leakage is apparently acceptable. Clutch/gearbox issue on the 2013 model, I had the factory fix but didn't made any difference. Later models have a brass valve inserted in that hole. The 2014 model was not better same shit clutch/gearbox issue. 2016 model massive improvement but not perfect. 2019 finally they cracked it.