If you can deal with setting it in a different way, the Thermoworks TimeStick would suit your purpose. It's designed as a cooking timer, so you set it to go off in "x" hours and "x" minutes. Instead of setting it to go off at 7am, you would set it to go off in 7 hours and 45 minutes (or whatever). It has the timer function and a clock function. The alarm has variable volume so you can make it louder or softer. It beeps for 60 seconds. After that, it beeps for 5 seconds every 30 seconds until you cancel the timer.
It weighs 1.7 ounces without the lanyard. 1.8 ounces with the detachable lanyard. Some of that weight is a refrigerator magnet glued into the back of it, which could probably be pried out if you really wanted to pare weight. I like the magnet (mine lives on the refrigerator door), so I'm not willing to sacrifice it to give you a weight savings! It runs on one large CR2032 watch battery.
It's splash-proof. You wouldn't want to swim with it, but a little rain or splashing would be fine.
When not camping, it makes the world's best timer for steaks on the grill, because you can put the damn thing around your neck, unlike normal kitchen timers that are always beeping inside when I'm outside or outside when I'm inside! I took mine car camping last week, using it to (go figure) time a rib eye steak.
This company makes high quality products. Nicer than the typical cheap plastic Chinese timers and similar gadgets.