Everyone in my neck of the woods use 100 watt bulbs to keep their well pumps from freezing in winter. LED? Yea right.
You can wire up 4 of them to get the same effect at lower voltage/wattage per bulb with the effect of the bulbs lasting many times longer. Wire two in series. This drops the wattage per bulb to 25W, but with two of them you're back to 50W, then wire two of the series combinations in parallel and you're back to 100 watts. Uses four bulbs, but lasts about 12 times longer than a single bulb because you're only running each bulb at 1/4 of its power rating.
I use 100 watt bulbs to keep my outside plants from freezing when the temps drop into the 20 or teens.
The big advantage of LED bulbs is 1) much lower power consumption. An LED bulb with the light of a 100W incandescent bulb will consume less than 15W. 2) They have a 100,000 hour life vs 5000 for an incandescent bulb (20X longer). Further, there is no single point failure, so they can continue to be used and degrade gracefully. Again, too expensive now, but once the price drops should be great.
Guess I don’t have your problem w/well pumps; I use my bulbs for light, not heat.