Here's my list of CD-4 capable cartridges, starting with the oldest: Audio Technica AT-14Sa, Audio Technica AT-15SS, Audio Technica AT-12S, Audio Technica AT 440ML, Grado Prestige Blue, Denon DL-110, Audio Technica VM 750SH. The last four weren't specifically designed for CD-4, but they work with certain caveats, save for the VM 750SH. The Grado has wide enough frequency response, but if you don't have good phono cables with low impedance it's performance is noisy, the same goes for the 440ML, of those two the 440ML is the best. The Denon works well enough until it's elliptical stylus gets about 200 hours of wear on it, and then it can't track the carrier on the inner grooves. That's a lot of listening, to be sure, but you'd have to use it for CD-4 only to extend it's useful life. The hands-down winner across the board, IMO, is the AT 750SH; in fact it's better than any of my vintage AT CD-4 cartridges ever were. I get no loss of the carrier on the inner grooves, and save for worn CD-4 records where the damage has been done, it's not noisy at all. It has a Shibata stylus, which I've found give better performance, and it's a stunningly good stereo cartridge to boot. So good, in fact, that I bought an extra one and a couple of replacement styli, just in case they quit making them. Notice that all of the early CD-4 cartridges that I own are all Audio-Technica. I've always liked their "house sound" and they were considered among the best, if not the best, CD-4 cartridges back in the day. The only one I bought new in the '70s was the 14Sa. I got it in the spring of 1975 when I bought a Pioneer Pl-10 turntable; the turntable cost around $100 and the cartridge was $75. A whopping price for a cartridge to a struggling college student. It's a great cartridge but styli are really hard to come by, though I do have two after-market spares made by Jico in Japan. Pickering made some good CD-4 cartridges, but they are rare as hen's teeth. I'd stick to getting the VM 750SH from Audio-Technica; yes it'll set you back $400, but I think it's a bargain at that price.
Edit: Oops! I forgot to mention the JVC 4MD20X. It's an excellent CD-4 cartridge also. It was made for them to their specs by Audio-Technica; at the time it was made it was considered the best of the CD-4 cartridges. I'm using it in my Dual 1229Q turntable and it's hooked up to my Lafayette LR-5000 receiver (their flagship model, IIRC) its CD-4 demodulator works very well with the JVC cartridge, far better than the AT-440ML ever did.