If your chinrest is way below your head and you're having to bend your neck over very far to get to it, it's too low, and yes, a chinrest should help that a lot.

The most common kind of chinrest should really be called a cheek rest, because the chin isn't involved at all.  There are other types where you actually use the chin. (I built a Sarasate style one out of a Guarneri.) You would have to turn your head farther to the left, but not tilt it as much. (If turning your head is as hard as tilting it, that won't help much.)

You might also check out a chiropractor. If the problem is 100% arthritis, they probably won't be able to help much, but the neck is part of the spine, and that's what they specialize in. I'm sure being able to move your head/Do you get neck tension more without pain would be nice in other areas than violin.

Finally, one last option - the only thing you need a chinrest for to begin with is for making large shifts from higher positions to lower ones.  There's almost always a way to make those transitions as a series of smaller transitions. You'll probably have to throw out the whole concept of "positions", because you might be playing the fourth finger in 7th position, the 3rd finger in 5th, the second finger in 3rd, and the first finger in first, as a way to move from 7th to 1st.

If you can do that, you don't need to put your chin/cheek on the violin at all. There will be a few pieces you won't be able to play that way (Say it's going from  G6 to A4), but not many.

You might want a shoulder rest to keep the violin from slipping down near your neck, but it probably isn't necessary.  I played for a couple of months with just the bare violin - no chinrest or shoulder rest. It wanting to slip down near my neck was the most common problem I encountered. Anything that provides friction between your shoulder and the violin should do the trick. (Pad, shoulder rest, whatever.)