Chris, ANY front disc calipers that you use will be an improvement over front drums.

There's an old saying, "You get what you pay for" and I'd be a little shy about paying only $400 for a complete disc brake conversion. Master Power Brakes offers the single piston conversion for your car for $849.95. Now you have to ask yourself, what could be different in the parts for a difference of $450? MP has been in business for a number of years and is recognized as a quality supplier of brake systems. What do you know about this other outfit? REMEMBER, these are BRAKES you're talking about, not some relatively unimportant item.

http://www.mpbrakes.com/db1741p.htm

http://www.mpbrakes.com/dr1700k.htm