Which tonearm with a Soundsmith The Voice?

Good question...and to cut to the chase...I don't know the answer. I have a similar table (technically, a Teres 245 w/ Verus motor) and a OL Silver tonearm. I have a medium-compliance SoundSmith Aida cartridge. Not sure if it's an optimal match, but it's what I've been using.

Due to the Voice's high compliance (22 or 28), the tonearm effective mass should be as low as possible. A great pairing should be the Funk F-XR which comes in 9" and 12" lengths at 8.5 grams and about 10 grams effective mass respectively.

My "The Voice" is the 22 compliance version.

I spotted a review of the Aida, another Cartridge from Soundsmith, with the same specs. It was very positive. The tonearm was the SAEC 407/23. Is this tonearm in production?

The SAEC 407/23 was made in 1980 and you can find details on it here for reference near the middle of the page. Used samples can usually be found on ebay.