I don't have information on that specific baler, but I have run an NH baler in the past. I think all NH balers use tines to feed the bale chamber as opposed to augers as do JD balers and many others.
For me the tines were never reliable for grass hay. I baled mostly Coastal Bermuda and some Bahia grass and the tines constantly jammed up with grass. I tried different arrangements for the tines with no luck. I went to a JD baler with an auger and could run all day long with no feed problems and only very occasional missed ties. It very well could be that an NH baler, even the one I had, could work well in Alfalfa or some such, but it just wasn't very good in the grass that I baled.
Although it was taxing my little tractor, I ran it with a Ford 3000 diesel. It was all it could do, but it ran it and ran it on minimal fuel. I wouldn't want to run it on anything any smaller. The 3000 is about a 43 HP tractor.
As far as buying used square balers go, you need to examine the bale chamber closely. Putting it away with a bale in the chamber and grass in the pickup area will ruin it very quickly. Hay will deposit an acid and destroy the bale box in short order. If the bale chamber is rusted and that's all that's wrong with it, you can build a new bale chamber pretty easily from steel plate, but you will need to get the baler cheap to allow for this.
Also, make sure that the vertical bolts that go down through wire grippers thread solidly into the plate below. When these threaded holes wear out, it's a mess to fix. I had to pull the whole tie mechanism apart, weld the holes and redrill and tap. The holes have to be PRECISELY placed and perfectly vertical for it to work right. I managed to do it iwth a drill press for drill bit and tap both, and got lucky. I had screwed up before doing this and got the bright idea to use helicoils. The helicoils could not even dream of holding up to the constant pounding.
Edit: I was in a hurry yesterday when I wrote the above, so I might add: My writings were assuming a wire tie baler. I'm not familar with the twine version.
Hope this helps.
