My top is a Robbins obtained from British Parts Northwest. Fits, looks fine (to me) and was cheap -- all I needed since I rarely use it, mainly in the boot just in case.
In case you don't know... do not discard the 3 stays across the front -- most tops do not come with these and at least some replacements out there are inferior to the original (not as stiff).
FWIW -- I kept my old top and cut out the rear window for a breezy but shady ride on long road trips in the sunny Southwest. Looks funky but rides cool. I live for the day when someone asks "How do you keep your rear window so clear?".