Other than taking it to a cobbler for stitching, how about some type of glue that would hold leather together? I just googled it and there's a glue called "Rapid Fuse" that supposedly is good for leather. Good luck !

Not sure glue would hold. So you have a handy relative or neighbor? My out-of-the-box solution is to have somebody put a rivet in that to hold it together.

Boston oak,

If you want to maintain the original aesthetics of your belt, you can get it stitched by a cobbler. Maybe spring for $6 to $10. If the holes from the previous stitching are intact, you could probably just get some carpet thread at JoAnn fabric or ask on FreeCycle - people have endless miscellaneous stuff they never use. You can get an inexpensive needle, maybe borrow a thimble, borrow a pair of pliers and your almost home. Wax the thread w a bit of beeswax or candle wax.

It looks like the leather is not all that tough -- unlike beg tanned or holster like leather. Got a buddy with a Kenmore, Singer or similar all metal sewing machine? Vintage. You might also beg a deal from an awning maker -- they have strong industrial machines and threads. Trade a batch of brownies, vacuuming, or lunch.

I'd take it to a shoe repair place....they have machines designed to sew leather and they don't charge very much.