I use some cheap 50 cm RGB lights (20€) for some years. I can't remember the name of it, but they work great. Maybe you should buy a bright torch with high CRI and a nice beam too. It is much easier and better for illuminating large rooms and landscapes and cars.
Besides the Helios 44 I use the Mir 1b. It is a great 37mm lens with a similar price to the Helios. The 12 mm Laowa is a great lens too but very expensive (1000 €).
It's always nice when people are infected with the light painting virus. 😉
those cheap ones usually have some random names :)
i was checking out Mir 1b years ago, it was a bit more expensive and harder to find than helios 44. At one time Helios 44 was everywhere and could be bought for 15$.
Light painting was always fun for me, as the results are something you "can't see with naked eye"