Current 'best' aftermarket non ac heater core?

Roll the dice....Spectra is a good one we used. 11 years now.
Honestly you would be better to get yours redone.
You quite possibly could get offshore junk or the bugger might not even fit.
**chi warranty also**
Do a search on here you will see read the aggravation people have had.
Steve's absolutely correct.

Spectra makes great quality products including their gas tanks. I've used both and they fit ,look and work perfect.

Also had old one redone and its sitting on a shelf just in case.