I guess a lot of it comes back to what your goals are vis a vis why you are sparring. When adding lots of safety gear or rules one has to constantly check to ensure the resulting fight looks like the fight you are training for. Too much restrictive gear and the sparring match no longer resembles an actual fight.
Note: a lot of padded staves out there are PVC cores with a thin layer of foam over it. They are too flimsy for the right feel, and they break easily. And when they break, they break in a way that usually leaves sharp points.
For weapons sparring take a look at what the FMA community does, many of the FMA guys already posting have given great advice. I'll add my two cents.
For weapons see what you can do to find a rattan staff. Rattan doesn't splinter like wood. Also, you can find rattan in a variety of thicknesses based on how real you want the sparring to be.
For pads: As mentioned, a fencing mask allows the most mobility from what i've seen. For maximum protection (that can be offered be a fencing mask) get a saber/three weapon mask, they can still be caved in by a heavy strike but are still quite resilient. If you want more of an armored head protection check out a WEKAF filipino martial arts sparring head gear. I've never used one but it appears to offer the impact resistance of kendo head gear but with less mobility restriction.
For elbows check out the better quality lacrosse pads. The higher quality lacrosse elbow pads are hard plastic (which can offer too much protection in some circles) but they have a flexible/ jointed elbow pad. The main problem I find with other elbow pads is that they restrict movement at the bicep/elbow joint. Check out a "Play it Again Sports" store for cheap used lacrosse elbow pads.
For gloves; hockey gloves will suffice but thumb movement and thus grip can be restricting. LAcrosse gloves offer the same protection but have more thumb mobility. Check out "Play it again Sports" for cheap used gloves. Other options are WEKAF competition gloves, the armored motorcycle gloves (ebay) or for minimal protection rugby gloves.
I'm still looking for decent leg protection especially an adequate knee pad that protects the sides of the knee. Possibly something jointed like the lacrosse elbow pads. Other hard plastic pads like catchers shin/knee guards seem to offer too much protection.
I train FMA regularly. I strive to find a fine line between reality and saftey in my sparring. I work a regular 9-5 job and can't go in with excessive bruises and can't afford to miss work due to injury. In the grand scheme of things my training will probably never be needed but I feel if I'm going to train I might as well know how to apply it to reality. I find fencing head gear, lacrosse elbow pads and gloves, and knee pads, with somewhat controlled sparring using a lighter rattan weapon 50%-70%ish power allow me to spar as much as I want.
Perhaps the most important thing to consider are your goals with sparring. DO you want to simulate reality? Do you simply want to practice defending against random attacks while still in "form"? Or do you want something in between?