Short answer is no.
Long answer:
I’m not sure why you’d use a flashlight head, you’d be better machining a custom LED heatsink and sourcing a suitable reflector.
The XHP70.3 tested here does 8700 lumens at 19A - this is a test bench value and bare LED values, expect up to 10% losses once the light passes through glass/lenses. Realistically, with adequate cooling you could get 6000 lumens out of one of these.
UHP bulbs have a much smaller light source area than LEDs, so (hypothetically) you’d end up with a less sharp image, possibly would be fixed with secondary optics but then you’ll have to design and machine custom parts to hold the optics, and source quality optics from somewhere…
If the custom fabrication of parts and sourcing optics (lens or reflectors), and the inferior focus hasn’t put you off yet, you’ll also likely need a new driver for the LEDs.