I am using 2 of these on my mountain bike. (I own 4 of them) $31 CAD each from amazon.ca. If they don't work for you, you can always use the free returns on Amazon.
FRIFLY Bike Headlight, 650 Feet Projection, 800 Lumens Super Bright, Aluminum alloy Shell , IPX6 Waterproof 5 Modes Bike Front Light USB Rechargeable, Mountable in Seconds. : Amazon.ca: Sports & Outdoors
May not be the best option, but it's an option. They may not stay level on your bars super well with technical riding.
I have them positioned above the brake lever reservoirs, so when they inevitably droop with a hard hit, the brake lever holds them up. I also cut off some of the excess plastic from the mounting thing because it's ridiculously long.
I find they're plenty bright even with just one running, but I can run 2 at low brightness and get by for a quite a few hours.
I also sometimes use a regular headlamp, meant for construction contractors on my helmet. This headlamp is my absolute favourite for anything and everything. Working on the car, working on the house, biking, camping.
Energizer Hard Case Professional 3 LED Headlight, Black/Gray : Amazon.ca: Tools & Home Improvement
It uses AA batteries instead of AAA like every other headlamp. The battery pack is on the back of your head, not the front, and it's is water resistant and shockproof. 3 straps instead of 2 for improved security.
$61 for 2 lights and $41 for a headlamp, $102 + tax from Amazon.ca.