If you dont want hydraulics, the conventinal screw style toplink is about the easiest thing manually. Okay, so it isnt fancy and doesn't ratchet, but it is the same as what you posted. A case of dont try to re-invent the wheel comes to mind.
And a bottle jack is single acting, so that wouldn't work either.
But if you are looking for something better and dont have the rear remotes, there is someting out there. The name of it slips me right now but it is a self contained hydraulic unit. Raise or lower the implement and open a little bypass valve to lengthen/shorten it. It is supposed to act like a shock absorber too. Bt someone else will probabally be along shorly with the name of it.