Here’s a link to a papyrus fragment from the De Corona from the first century BCE. You may have to use the enlarging tool to bring it up to full size; once you do it’s more or less legible:
http://library.princeton.edu/libraries/firestone/rbsc/aids/papyri/images/Demosthenes.jpg
Demosthenes, De corona, 167-169. AM 9051 (=P. Oxy. XI 1377), I c. BC
It’s from this Princeton website; you can find the citation by clicking on the link and then clicking on “Digital Images of Selected Princeton Papyri.” Digital images of other papyri are available on the site, too.
http://library.princeton.edu/libraries/firestone/rbsc/aids/papyri/
The text of the papyrus begins in the middle of the spurious “Reply” of Philip to the Thebans at 167. This is one of the spurious documents added to the text in places where Demosthenes calls for the clerk to read a document. These documents appear in some but not all of the manuscripts, presumably reflecting two manuscript traditions that diverged in antiquity. The well-established consensus is that they are not genuine, but were added at some later date.
Here is the legible portion from the online version at the Perseus website (you can find a translation there, too):
167 . . . ἑτέρων ἐπακολουθεῖν γνώμαις, ἥσθην καὶ μᾶλλον ὑμᾶς ἐπαινῶ κατὰ πολλά, μάλιστα δ᾽ ἐπὶ τῷ βουλεύσασθαι περὶ τούτων ἀσφαλέστερον καὶ τὰ πρὸς ἡμᾶς ἔχειν ἐν εὐνοίᾳ: ὅπερ οὐ μικρὰν ὑμῖν οἴσειν ἐλπίζω ῥοπήν, ἐάν περ ἐπὶ ταύτης μένητε τῆς προθέσεως. ἔρρωσθε.
168 οὕτω διαθεὶς ὁ Φίλιππος τὰς πόλεις πρὸς ἀλλήλας διὰ τούτων καὶ τούτοις ἐπαρθεὶς τοῖς ψηφίσμασιν καὶ ταῖς ἀποκρίσεσιν, ἧκεν ἔχων τὴν δύναμιν καὶ τὴν Ἐλάτειαν κατέλαβεν, ὡς οὐδ᾽ ἂν εἴ τι γένοιτ᾽ ἔτι συμπνευσάντων ἂν ἡμῶν καὶ τῶν Θηβαίων.
168, the genuine Demosthenic text, begins at line 12 with the word ουτωc (οὕτω in modern editions). The word ἔρρωσθε which appears in modern texts based on the manuscript tradition at the end of the spurious response of Philip does not seem to appear in the papyrus.
One item of interest (to me at least) is the spelling υμειν for ὑμῖν at the beginning of line 9. Does that suggest that the merger of ει with ι was already underway?