Last year, on July 20, 2023 I found out where in Madrid these could be purchased and the prices, yesterday, September 4, 2024 I learned of the Parisian shipments early on, as the Dionisio Aguado invention initially was announced on May 16, 1838. There are 14 mentions of this device in the dailies all the way to May 20, 1853. In the newspaper image page the text will be found in the right column, just below the the center. To find the original large article, scroll quite a bit down, I have written 50 articles since then DIONISIO AGUADO (1784-1849) AND THE 1838 GUITAR TRIPOD.
This from the daily: "Diario de avisos de Madrid" November 22, 1838 page 2
Se acaba de recibir de Paris una remesa
de TRIPODISONES o maquinas donde se
colocala guitarra para aumentar su voz y
facilitar la ejecucion del tocador. Dicha
maqiina es inventada por Don Dionisio Aguado,
y la han adoptado los mas celebres
guiitarristas. Se hallan de venta en esta corte
en la guitarreria de Campo.