Perhaps one of these sites could refer you to a conservator?

http://www.conservation-us.org/membership/find-a-conservator#.WJncV3BMUnI
This is the site for the American Institute of Conservation's "Find a Conservator" page.

Otherwise, you could try contacting one of the following companies, maybe they have a history of conserving one of his works.
https://www.vallejogallery.com/artist.php?name=Thomas_Willis&id=78Phone: (949) 642-7945 | E-mail: [log in to unmask]
http://www.pbs.org/wgbh/roadshow/season/17/myrtle-beach-sc/appraisals/willis-painting-with-silk-work-ca-1910--201202A33/

https://www.skinnerinc.com/auctions/2880B/lots/427

http://landandseacollection.com/id876.htmlhttp://www.landandseacollection.com/
Elinor Dei Tos Pironti
[log in to unmask] am just beginning a small textile conservation business.
Good luck with your search.

      From: TEXCONS automatic digest system <[log in to unmask]>
 To: [log in to unmask] 
 Sent: Tuesday, February 7, 2017 4:49 AM
 Subject: TEXCONS Digest - 4 Feb 2017 to 7 Feb 2017 - Special issue (#2017-3)
   
There is 1 message totaling 75026 lines in this issue.

Topics in this special issue:

  1. silk ship portrait

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Date:    Tue, 7 Feb 2017 10:39:32 +0100
From:    "[log in to unmask]" <[log in to unmask]>
Subject: silk ship portrait


Hello,

I
am working on the attaced silk ship portrait (Brigantino, Fortunato
Repetto) by the New York's artist Thomas Willis (1850-1925) from the
Maritime Museum in Camogli, Italy; someone knows if there are Museums
with similar portraits and if they have had a conservation treatments
and dyes identifications?

Thank
you very much for your help.
Claudia
Santamaria

Genova


Italy


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End of TEXCONS Digest - 4 Feb 2017 to 7 Feb 2017 - Special issue (#2017-3)
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