Can envlab create a pdf page the size of the desired envelope?

This question is similar to this one, but apparently not similar enough to warrant a straight edit. Thus, I pose it as a new question.

When using envlab with pdflatex via MiKTeX and TeXstudio, I would like for the page size of the pdf to be the actual size of the envelope. The following prints both the letter and the envelope on letter-sized paper:

\documentclass{letter}
\topmargin=-1in
\textheight=5.5in
\oddsidemargin=0pt
\textwidth=6.5in

\usepackage[T1]{fontenc}
\usepackage{lmodern}
\makelabels

\begin{document}

\signature{Peter Schilling}

\begin{letter}{1111 1st Ave\\1, IA 11111}

\opening{To whom it may concern:}

23456789

\closing{Thank you,}

\end{letter}

\end{document}


When then trying to print on the envelope, the printer (through Acrobat, in this case) either wants to shrink the entire page to fit, making the output too small:

or only print what fits on the envelope from the upper left:

I'm not exactly sure what's going on, but I'll suggest a workaround. Just change the page geometry before the labels are printed:

\documentclass{letter}
\topmargin=-1in
\textheight=5.5in
\oddsidemargin=0pt
\textwidth=6.5in
\usepackage[T1]{fontenc}
\usepackage{lmodern}

\AtBeginLabels{%
\eject \pdfpagewidth=\EnvelopeHeight \pdfpageheight=\EnvelopeWidth%
}
\makelabels

\begin{document}
\signature{Peter Schilling}