I've got several Lee filters with holder by the manufacturer. I'm looking for a hood, but the one sold by Lee is very expensive.
Did anybody find a cheaper alternative?
The purpose of the lens hood is to cast a shadow on the lens so that the only light being picked up is the light you're pointing the lens at - any glare causing strays get blocked.
Hoods are super useful when you are chasing the action. But, when you slow down to shoot a long exposure, a dedicated hood really isn't necessary anymore.
All you need to do is cast a shadow onto your lens and block those stray glare-causing rays.
And for this, you can use almost anything. If the sun is low in the sky, your body might be a good option. Reflector/Scrim/T-shirt/Rain Cover/Tarp/Umbrella...anything that you can find will just about work. Bonus points for you and your arms if you can find a way to rig it to stay in place. (Do keep in mind that you don't want to rig it to the tripod, as any wind will send your rig runnin')