I'm looking to replace the hose (actually I only really need a new head) on
my Zefal Husky. The head is the Schrader with thumb-lock variety that has an
adaptor for presta. The rubber washer/grommet/seal on the presta adapter
wears quickly and leaks constantly so I'm interested in a new head with thumb-lock that
automatically adapts to both valve types and that does not rely only on
friction to stay on and form a seal. Something like the head on my new Zefal HPX
frame pump. I do need a hose/head combo for both valve types and am seeking
recommendations. Thanks.

You might want to consider Topeak's Smart Head or Twin Head - claims to fit every pump out there.

https://www.topeak.com/products/Floor...HeadUpgradeKit
https://www.topeak.com/products/Floor...HeadUpgradeKit

My ride bud just got one and it works fine.

Check your LBS. I used to keep a pump head or two on hand. Cut about 1/2" from your existing hose and clamp the new one on with a tiny hose clamp. Cost should be >$5.00.

I just got a rebuild kit for my 20 year old Zefal and a new hose with head here.
https://www.xxcycle.com/parts-pumps-foot,en.php
Very good service.

https://www.biketoolsetc.com/index.cg...tem_id=SK-3176
https://www.biketoolsetc.com/index.cg...tem_id=SK-3203

https://www.silcapompe.it/adaptors_en.htm Silca #40.0

https://www.jitensha.com/eng/hiramepumphds.html

This worked for me with a big floor pump. The head in the kit my LBS sold me works on my bikes and my big truck with no changes. The kit even included the tiny little pipe clamp.

+1, I put one of these on my Parktools floor pump with a dual head & works real well