Also, when working with high-powered LEDs, you'll probably need to investigate the proper amount of heat-sinking that's needed to keep the LED under a safe temperature (<150 degrees C is typical).

I am guessing that the superbrightleds.com PR-style 1W LEDs will fit anything that takes a PR bulb, and does not have heatsink issues. Sure, the beam shape may be different due to LED directionality. FWIW, Terralux sells a 1 W LED that puts out 50 lumens.