Citabrias as $150/hr, Pitts at $330/hr
Wow! Attitude charges about $90 for a Citabria, $220 for the Pitts. Instruction varies with the instructor, $60-75. And they're in the same hangar. With what you save on learning to fly the Pitts, you can pay for an hour in the L-39 (~$2200 depending on the fuel price on the day).
As for doing a tailwheel conversion in the Pitts... I guess anything is possible, like learning to drive in a vintage Ferrari. The first 50 or so landings in the Pitts are terrifying even when you're comfortable with tailwheel landings. Unless you're really a natural genius then I'd be sure it'll be both quicker and cheaper to do the conversion in something that flies more like an aeroplane and less like a brick.
n5296s