Sanskritweb, maintained by Ulrich Stiehl, Heidelberg (Germany), has links to large-print editions of the Gita. Here is the information from his website:
“This large-print Devanagari edition also including the transliterated text and downloadable as Gita-big.pdf (560 KB, 117 pages, 1 column) is designed for (a) readers with bad eyesight, (b) learners of the Devanagari script, (c) designers interested in Devanagari calligraphy. The Devanagari text of this large-print edition is typeset in 24 point “Sanskrit 2003” on 32 point body.
Readers with better eyesight may download the file Gita-2up.pdf (630 KB, 54 pages, 2 columns) with same contents as file gita-big.pdf. The Devanagari text of file gita-2up.pdf is typeset in ca. 17 point, due to format reduction to ca. 71% from DIN A4 to DIN A5.
For comparison, we also offer the Devanagari-only file Gita-dev.pdf (290 KB, 22 pages, 2 columns) typeset in 12 point Devanagari. Europeans with normal eyesight, who are accustomed to the Latin script, usually consider 12 point Devanagari as “very small print”, whereas they consider 12 point Latin as “quite normal print”.”