i have bought last year such a clutch tamliya for 180€ you can try to lower the price a bit, later on i go build in the dmd and mf unit in it but although it is a clutch system it works very well. Compared to my FO ardennes KT Henshell late it runs very well but no noise are recoil but on ebay i had bought the systen new for 30€, i now looking for the MF and DMD controllers.
300$ is a nice price when its in mint condition, just buy it but try to get a bit lower the price