I was a brake tester for 13 years and part time crash investigator. When truck brakes fail it is not nice. What is posted above is correct.

The front brakes provide anything up to 100% (stoppie) of the deceleration forces on a bike simply because the front loads up and the rear unloads quite significantly. Ride like you have only half the braking available and you will not be short of mechanical advantage. Look at all the cruiser riders too terrified to even touch the front brake that survive for years using about a tenth of what they have.

Backing material will chew up the disc, so just don't use the worn brake unless those last few fractions of decel are going to make a trashed disc the least of your worries.

We stopped riveting friction material to shoes (I've never seen it done to a pad) for commercial, employee safety and vehicle safety reasons. I have seen rivets fail and the friction surface fall off, jam the brake on and set the hub on fire. That would be lethal on a bike. I dread to think what sort of adhesives would be used, but anyone daft enough try gets what they deserve (the pad factories control the surface finish, temperature, humidity and all sorts when they bond friction material in it's part finished state to the backing) . They are probably the same idiots who will give themselves lung disease by drilling and cutting pads to shape. The latter might work, so long as the pad is free to float if it works once it'll work again. It is still an untested bodge.

Any "mechanic" who is handed pads and can't change them is best avoided. On the Wee you remove the calliper (one bolt and a sliding pin), push the pads back, remove a slot headed cover, remove an allen headed pin, collect the old pads and spring from where they shot out and fit the new ones in reverse order. Takes ten minutes using the tool kit Suzuki supplied. If you buy pads you also want to buy copper grease to go on the back of the new pads, multi-purpose grease for all the pins and sliders and something like brake spray or petrol to clean off all the dust and gunk. This is similar

Howto: Replace Motorcycle Rear Brake Pads in 10 mins ('09 Ninja 250) - YouTube

I'd ride the 1000 Km and just keep 4 seconds from the vehicle in front.

Good Luck and Enjoy your trip.

Andy