Re: looking for a true sounding harmonizer/doubler
The only possible alternatives are the old IVL units from Digitech. Those are a cut above anything else except Eventide, but still a definite cut below Eventide. They were made in the early 90's, and there were a few units you might be able to score on the bay. I got a studio 5000 for a couple hundred.
IPS33 - the original. 15k frequency response, not such a great unit.
IPS33B - better unit. Very good.
DHP33 - same hardware as the IPS33B
DHP55 - fancier than the 33 units, this has more harmonies & reverb/FX programs. Still the same overall sound quality though.
Studio 5000 - same hardware as the DHP55.