Reddit mentions of Slime Self-Healing 26/1.75-2.125 Bicycle Tube with PRESTA VALVE

Solid tires look interesting in concept ... in reality there's a lot wrong with them. You will almost certainly be dissatisfied.

A solid tire completely changes the way forces are distributed around the rim. With an air-filled tire, impact forces are distributed around the wheel, unless you hit something hard enough that the wheel actually makes contact through the tire. With solid tires, all of those forces are delivered through the tire directly to the wheel at the point of contact. The net result is that although the tire will absorb some of the impact forces, the wheel is ultimately taking more abuse than it was designed to.

So, while you may save time/money on tubes ... you'll be having a tough time keeping your wheels true, and will be wasting time and money re-trueing and/or replacing wheels. There really is a reason you don't often see these solid tires out in the wild.

Instead, you should look into some of the more "conventional" options.

1. Try a super puncture-resistant tire like a Schwalbe Marathon or the like.
   
2. You could add a "slime tube". These tubes are filled with a liquid that will instantly seal moderately sized punctures. It won't work for pinch flats, but if you're suffering from punctures through the tread or sidewall, these will work fairly well.
   
3. You could go tubeless. You'll need to buy a set of tubeless-ready wheels and a tubeless ready set of tires. Once mounted, you add a few ounces of tubeless tire sealant. Pinch flats are now a thing of the past, and good tubeless tire sealant will seal holes up to 1/4" in diameter. This is your most expensive route, but it's also your most robust solution. NOTE: Some people get away with "ghetto tubeless" where a "standard" rim is made airtight using extra layers of tubeless rim tape and then mount a tubeless ready tire. At the lower pressures of a 26x2 tire, you can sometimes get away with it. That said, initial setup will be fiddly, so you'd either have to be comfortable fiddling around with a project that's going to be a bit of a pain in the ass ... or know someone who is.