The translation of the Mahavastu (Mvu) is available on archive.org as a scanned pdf. But their pdfs, while good quality, use three layers of images, and are slow and resource heavy to use, even on a reasonably powerful PC. You know what it’s like when you try to go forward a couple of pages and sit and wait for the page to display?
I extracted the text images and compiled them as searchable PDFs, which are much more responsive. Here’s the three volumes.
mvu1.pdf (49.7 MB)
mvu2.pdf (38.0 MB)
mvu3.pdf (33.3 MB)