I wouldn't just go and buy some new lifters...I'd find out first why the engine had no oil in it.
Your lifters are hydraulic, and when normal engine oil pressure is produced, they "pump up", thereby creating a cushion of oil that eliminates most of the valvetrain noise.
There may be a reason why they're not pumping up...Low oil pressure (which could be caused by a number of reasons), plugged oil galleries or any number of other restrictions in the oiling system which could be as simple as a clogged pickup screen or a plugged oil filter.
Rather than just throwing parts at it, find out what the root of the problem is first, then attack it from there.
First thing on my mind would be why was it out of oil in the first place? If you have an oil drinker, now combined with abnormal noise, you'd probably be better off just getting a nice low-mileage engine from a salvage yard, and replacing it.