It would be hard to say, unless you're in touch with all the collections.
You can find these by using the search string "Gene Autry recording
archives" for a Google search.

Paul T. Jackson
Trescott Research
Steilacoom, WA 98338
[log in to unmask]
trescottresearch.com

On Tue, Jun 12, 2018, 10:30 AM Malcolm <[log in to unmask]> wrote:

> Who holds the most complete collection of Gene Autry 78s?
> Autry began by recording for Victor on Oct. 9, 1929. His steel
> guitar playing accompanist was Frank Marvin who played in
> both Hawaiian and Country styles. I want to know how long it
> took Marvin to morph from mostly a Hawaiian style to what came
> to be considered a Country style. As of March 1937 he was still
> using an acoustic steel guitar; as of June 1937 he began recording
> with an electric (or electrified acoustic?) steel guitar which he
> continued using until 1942 (ref. Tony Russell) and possibly beyond.
> I've been adding to the Hawaiian discog regularly since publication
> (has it really been more than 10 years?) and would like to flesh out
> Autry's listing.
> Malcolm
>