I have been using this timer for some time both in the kitchen and at the range and have had many inquiries as to where to get one. While a little pricey these timers can clearly be heard from one end of the line to the other and the numbers are big and easy to see. I modified mine to add a lanyard but the company does make other timers with a lanyard attached. I don't advise buying from Amazon or Ebay as the prices are much higher than directly from the company. Here you go: https://www.thermoworks.com/Extra-Big-Loud (https://www.thermoworks.com/Extra-Big-Loud)
Another option I like is called GymBoss miniMax. You can program multiple timers and save them and the alarms can be set to vibrate only. So I have a timer set up for stage 2 which vibrates for one second at 45 seconds (a 10 second warning) and a final 1 second vibrating warning at 55 seconds. I clip the timer onto my pants pocket and it doesn't make a lot of noise and disturb anyone else. It also helps keep my practice sessions honest by keeping good time. I also have a program set up the same way for stage 3 with a warning at 55 seconds and 65 seconds. Another bonus is if you shoot high power, the timer is legal because it can be set up to vibrate only.