I have several different brands. I like the ones with big silver shades, as they have a nice wide basking area. Mine were from a poultry site, I think they're called inteflec?
I also like the silver conical "pig lamps" (they don't go out if you accidentally knock them!). Mine are "wolsley stockshop".
Which ever you go with check it's rated for a high enough wattage & has a ceramic figment, not plastic.